Apache HTTP Server Version 2.4

Apache > HTTP Server > Documentation > Version 2.4 > Modules

# Apache Module mod_mime

Description: | Associates the requested filename's extensions with the file's behavior (handlers and filters) and content (mime-type, language, character set and encoding)
Status: | Base
Module Identifier: | mime_module
Source File: | mod_mime.c

### Summary

This module is used to assign content metadata to the content selected for an HTTP response by mapping patterns in the URI or filenames to the metadata values. For example, the filename extensions of content files often define the content's Internet media type, language, character set, and content-encoding. This information is sent in HTTP messages containing that content and used in content negotiation when selecting alternatives, such that the user's preferences are respected when choosing one of several possible contents to serve. See `mod_negotiation` for more information about content negotiation.

The directives `AddCharset`, `AddEncoding`, `AddLanguage` and `AddType` are all used to map file extensions onto the metadata for that file. Respectively they set the character set, content-encoding, content-language, and media-type (content-type) of documents. The directive `TypesConfig` is used to specify a file which also maps extensions onto media types.

In addition, `mod_mime` may define the handler and filters that originate and process content. The directives `AddHandler`, `AddOutputFilter`, and `AddInputFilter` control the modules or scripts that serve the document. The `MultiviewsMatch` directive allows `mod_negotiation` to consider these file extensions to be included when testing Multiviews matches.

While `mod_mime` associates metadata with filename extensions, the `core` server provides directives that are used to associate all the files in a given container (e.g., `<Location>`, `<Directory>`, or `<Files>`) with particular metadata. These directives include `ForceType`, `SetHandler`, `SetInputFilter`, and `SetOutputFilter`. The core directives override any filename extension mappings defined in `mod_mime`.

Note that changing the metadata for a file does not change the value of the `Last-Modified` header. Thus, previously cached copies may still be used by a client or proxy, with the previous headers. If you change the metadata (language, content type, character set or encoding) you may need to 'touch' affected files (updating their last modified date) to ensure that all visitors are receive the corrected content headers.

### Topics

- Files with Multiple Extensions
- Content encoding
- Character sets and languages

### Directives

### Bugfix checklist

- httpd changelog
- Known issues
- Report a bug

### See also

- `MimeMagicFile`
- `AddDefaultCharset`
- `ForceType`
- `SetHandler`
- `SetInputFilter`
- `SetOutputFilter`

## Files with Multiple Extensions

Files can have more than one extension; the order of the extensions is normally irrelevant. For example, if the file `welcome.html.fr` maps onto content type `text/html` and language French then the file `welcome.fr.html` will map onto exactly the same information. If more than one extension is given that maps onto the same type of metadata, then the one to the right will be used, except for languages and content encodings. For example, if `.gif` maps to the media-type `image/gif` and `.html` maps to the media-type `text/html`, then the file `welcome.gif.html` will be associated with the media-type `text/html`.

Languages and content encodings are treated accumulative, because one can assign more than one language or encoding to a particular resource. For example, the file `welcome.html.en.de` will be delivered with `Content-Language: en, de` and `Content-Type: text/html`.

Care should be taken when a file with multiple extensions gets associated with both a media-type and a handler. This will usually result in the request being handled by the module associated with the handler. For example, if the `.imap` extension is mapped to the handler `imap-file` (from `mod_imagemap`) and the `.html` extension is mapped to the media-type `text/html`, then the file `world.imap.html` will be associated with both the `imap-file` handler and `text/html` media-type. When it is processed, the `imap-file` handler will be used, and so it will be treated as a `mod_imagemap` imagemap file.

If you would prefer only the last dot-separated part of the filename to be mapped to a particular piece of meta-data, then do not use the `Add*` directives. For example, if you wish to have the file `foo.html.asis` served by the `send-as-is` handler provided by `mod_asis` script, but not the file `bar.asis.html`, then instead of using `AddHandler send-asis .asis`, use

### Configure handler based on final extension only

    <FilesMatch "[^.]+\.asis$">
      SetHandler send-asis
    </FilesMatch>

## Content encoding

A file of a particular media-type can additionally be encoded a particular way to simplify transmission over the Internet. While this usually will refer to compression, such as `gzip`, it can also refer to encryption, such a `pgp` or to an encoding such as UUencoding, which is designed for transmitting a binary file in an ASCII (text) format.

The HTTP/1.1 RFC (RFC 2616), section 14.11 puts it this way:

> The Content-Encoding entity-header field is used as a modifier to the media-type. When present, its value indicates what additional content codings have been applied to the entity-body, and thus what decoding mechanisms must be applied in order to obtain the media-type referenced by the Content-Type header field. Content-Encoding is primarily used to allow a document to be compressed without losing the identity of its underlying media type.

By using more than one file extension (see section above about multiple file extensions), you can indicate that a file is of a particular type, and also has a particular encoding.

For example, you may have a file which is a Microsoft Word document, which is pkzipped to reduce its size. If the `.doc` extension is associated with the Microsoft Word file type, and the `.zip` extension is associated with the pkzip file encoding, then the file `Resume.doc.zip` would be known to be a pkzip'ed Word document.

Apache sends a `Content-encoding` header with the resource, in order to tell the client browser about the encoding method.

    Content-encoding: pkzip

## Character sets and languages

In addition to file type and the file encoding, another important piece of information is what language a particular document is in, and in what character set the file should be displayed. For example, the document might be written in the Vietnamese alphabet, or in Cyrillic, and should be displayed as such. This information, also, is transmitted in HTTP headers.

The character set, language, encoding and mime type are all used in the process of content negotiation (See `mod_negotiation`) to determine which document to give to the client, when there are alternative documents in more than one character set, language, encoding or mime type. All filename extensions associations created with `AddCharset`, `AddEncoding`, `AddLanguage` and `AddType` directives (and extensions listed in the `MimeMagicFile`) participate in this select process. Filename extensions that are only associated using the `AddHandler`, `AddInputFilter` or `AddOutputFilter` directives may be included or excluded from matching by using the `MultiviewsMatch` directive.

### Charset

To convey this further information, Apache optionally sends a `Content-Language` header, to specify the language that the document is in, and can append additional information onto the `Content-Type` header to indicate the particular character set that should be used to correctly render the information.

`Content-Language: en, fr Content-Type: text/plain; charset=ISO-8859-1`

The language specification is the two-letter abbreviation for the language. The `charset` is the name of the particular character set which should be used.

## AddCharset Directive

Description: | Maps the given filename extensions to the specified content charset
Syntax: | `AddCharset charset extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `AddCharset` directive maps the given filename extensions to the specified content charset (the Internet registered name for a given character encoding). charset is the media type's charset parameter for resources with filenames containing extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension.

### Example

    AddLanguage ja .ja
    AddCharset EUC-JP .euc
    AddCharset ISO-2022-JP .jis
    AddCharset SHIFT_JIS .sjis

Then the document `xxxx.ja.jis` will be treated as being a Japanese document whose charset is `ISO-2022-JP` (as will the document `xxxx.jis.ja`). The `AddCharset` directive is useful for both to inform the client about the character encoding of the document so that the document can be interpreted and displayed appropriately, and for content negotiation, where the server returns one from several documents based on the client's charset preference.

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

### See also

- `mod_negotiation`
- `AddDefaultCharset`

## AddEncoding Directive

Description: | Maps the given filename extensions to the specified encoding type
Syntax: | `AddEncoding encoding extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `AddEncoding` directive maps the given filename extensions to the specified HTTP content-encoding. encoding is the HTTP content coding to append to the value of the Content-Encoding header field for documents named with the extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension.

### Example

    AddEncoding x-gzip .gz
    AddEncoding x-compress .Z

This will cause filenames containing the `.gz` extension to be marked as encoded using the `x-gzip` encoding, and filenames containing the `.Z` extension to be marked as encoded with `x-compress`.

Old clients expect `x-gzip` and `x-compress`, however the standard dictates that they're equivalent to `gzip` and `compress` respectively. Apache does content encoding comparisons by ignoring any leading `x-`. When responding with an encoding Apache will use whatever form (i.e., `x-foo` or `foo`) the client requested. If the client didn't specifically request a particular form Apache will use the form given by the `AddEncoding` directive. To make this long story short, you should always use `x-gzip` and `x-compress` for these two specific encodings. More recent encodings, such as `deflate`, should be specified without the `x-`.

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

## AddHandler Directive

Description: | Maps the filename extensions to the specified handler
Syntax: | `AddHandler handler-name extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

Files having the name extension will be served by the specified handler-name. This mapping is added to any already in force, overriding any mappings that already exist for the same extension. For example, to associate `.var` files with the `type-map` handler provided by `mod_negotiation`, you might use:

    AddHandler type-map .var

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

### See also

- `SetHandler`
- `FallbackResource`

## AddInputFilter Directive

Description: | Maps filename extensions to the filters that will process client requests
Syntax: | `AddInputFilter filter[;filter...] extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

`AddInputFilter` maps the filename extension extension to the filters which will process client requests and POST input when they are received by the server. This is in addition to any filters defined elsewhere, including the `SetInputFilter` directive. This mapping is merged over any already in force, overriding any mappings that already exist for the same extension.

If more than one filter is specified, they must be separated by semicolons in the order in which they should process the content. The filter is case-insensitive.

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

### See also

- `RemoveInputFilter`
- `SetInputFilter`

## AddLanguage Directive

Description: | Maps the given filename extension to the specified content language
Syntax: | `AddLanguage language-tag extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `AddLanguage` directive maps the given filename extension to the specified content language. Files with the filename extension are assigned an HTTP Content-Language value of language-tag corresponding to the language identifiers defined by RFC 3066. This directive overrides any mappings that already exist for the same extension.

### Example

    AddEncoding x-compress .Z
    AddLanguage en .en
    AddLanguage fr .fr

Then the document `xxxx.en.Z` will be treated as being a compressed English document (as will the document `xxxx.Z.en`). Although the content language is reported to the client, the browser is unlikely to use this information. The `AddLanguage` directive is more useful for content negotiation, where the server returns one from several documents based on the client's language preference.

If multiple language assignments are made for the same extension, the last one encountered is the one that is used. That is, for the case of:

    AddLanguage en .en
    AddLanguage en-gb .en
    AddLanguage en-us .en

documents with the extension `.en` would be treated as being `en-us`.

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

### See also

- `mod_negotiation`

## AddOutputFilter Directive

Description: | Maps filename extensions to the filters that will process responses from the server
Syntax: | `AddOutputFilter filter[;filter...] extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `AddOutputFilter` directive maps the filename extension extension to the filters which will process responses from the server before they are sent to the client. This is in addition to any filters defined elsewhere, including `SetOutputFilter` and `AddOutputFilterByType` directive. This mapping is merged over any already in force, overriding any mappings that already exist for the same extension.

For example, the following configuration will process all `.shtml` files for server-side includes and will then compress the output using `mod_deflate`.

    AddOutputFilter INCLUDES;DEFLATE shtml

If more than one filter is specified, they must be separated by semicolons in the order in which they should process the content. The filter argument is case-insensitive.

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

Note that when defining a set of filters using the `AddOutputFilter` directive, any definition made will replace any previous definition made by the `AddOutputFilter` directive.

    # Effective filter "DEFLATE"
    AddOutputFilter DEFLATE shtml
    <Location "/foo">
      # Effective filter "INCLUDES", replacing "DEFLATE"
      AddOutputFilter INCLUDES shtml
    </Location>
    <Location "/bar">
      # Effective filter "INCLUDES;DEFLATE", replacing "DEFLATE"
      AddOutputFilter INCLUDES;DEFLATE shtml
    </Location>
    <Location "/bar/baz">
      # Effective filter "BUFFER", replacing "INCLUDES;DEFLATE"
      AddOutputFilter BUFFER shtml
    </Location>
    <Location "/bar/baz/buz">
      # No effective filter, replacing "BUFFER"
      RemoveOutputFilter shtml
    </Location>

### See also

- `RemoveOutputFilter`
- `SetOutputFilter`

## AddType Directive

Description: | Maps the given filename extensions onto the specified content type
Syntax: | `AddType media-type extension [extension] ...`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `AddType` directive maps the given filename extensions onto the specified content type. media-type is the media type to use for filenames containing extension. This mapping is added to any already in force, overriding any mappings that already exist for the same extension.

It is recommended that new media types be added using the `AddType` directive rather than changing the `TypesConfig` file.

### Example

    AddType image/gif .gif

Or, to specify multiple file extensions in one directive:

### Example

    AddType image/jpeg jpeg jpg jpe

The extension argument is case-insensitive and can be specified with or without a leading dot. Filenames may have multiple extensions and the extension argument will be compared against each of them.

A similar effect to `mod_negotiation`'s `LanguagePriority` can be achieved by qualifying a media-type with `qs`:

### Example

    AddType application/rss+xml;qs=0.8 .xml

This is useful in situations, e.g. when a client requesting `Accept: */*` can not actually processes the content returned by the server.

This directive primarily configures the content types generated for static files served out of the filesystem. For resources other than static files, where the generator of the response typically specifies a Content-Type, this directive has no effect.

### Note

If no handler is explicitly set for a request, the specified content type will also be used as the handler name.

When explicit directives such as `SetHandler` or `AddHandler` do not apply to the current request, the internal handler name normally set by those directives is instead set to the content type specified by this directive.

This is a historical behavior that may be used by some third-party modules (such as mod_php) for taking responsibility for the matching request.

Configurations that rely on such "synthetic" types should be avoided. Additionally, configurations that restrict access to `SetHandler` or `AddHandler` should restrict access to this directive as well.

### See also

- `ForceType`
- `mod_negotiation`

## DefaultLanguage Directive

Description: | Defines a default language-tag to be sent in the Content-Language header field for all resources in the current context that have not been assigned a language-tag by some other means.
Syntax: | `DefaultLanguage language-tag`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `DefaultLanguage` directive tells Apache that all resources in the directive's scope (e.g., all resources covered by the current `<Directory>` container) that don't have an explicit language extension (such as `.fr` or `.de` as configured by `AddLanguage`) should be assigned a Content-Language of language-tag. This allows entire directory trees to be marked as containing Dutch content, for instance, without having to rename each file. Note that unlike using extensions to specify languages, `DefaultLanguage` can only specify a single language.

If no `DefaultLanguage` directive is in force and a file does not have any language extensions as configured by `AddLanguage`, then no Content-Language header field will be generated.

### Example

    DefaultLanguage en

### See also

- `mod_negotiation`

## ModMimeUsePathInfo Directive

Description: | Tells `mod_mime` to treat `path_info` components as part of the filename
Syntax: | `ModMimeUsePathInfo On|Off`
Default: | `ModMimeUsePathInfo Off`
Context: | directory
Status: | Base
Module: | mod_mime

The `ModMimeUsePathInfo` directive is used to combine the filename with the `path_info` URL component to apply `mod_mime`'s directives to the request. The default value is `Off` - therefore, the `path_info` component is ignored.

This directive is recommended when you have a virtual filesystem.

### Example

    ModMimeUsePathInfo On

If you have a request for `/index.php/foo.shtml` `mod_mime` will now treat the incoming request as `/index.php/foo.shtml` and directives like `AddOutputFilter INCLUDES .shtml` will add the `INCLUDES` filter to the request. If `ModMimeUsePathInfo` is not set, the `INCLUDES` filter will not be added. This will work analogously for virtual paths, such as those defined by `<Location>`

### See also

- `AcceptPathInfo`

## MultiviewsMatch Directive

Description: | The types of files that will be included when searching for a matching file with MultiViews
Syntax: | `MultiviewsMatch Any|NegotiatedOnly|Filters|Handlers [Handlers|Filters]`
Default: | `MultiviewsMatch NegotiatedOnly`
Context: | server config, virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

`MultiviewsMatch` permits three different behaviors for mod_negotiation's Multiviews feature. Multiviews allows a request for a file, e.g. `index.html`, to match any negotiated extensions following the base request, e.g. `index.html.en`, `index.html.fr`, or `index.html.gz`.

The `NegotiatedOnly` option provides that every extension following the base name must correlate to a recognized `mod_mime` extension for content negotiation, e.g. Charset, Content-Type, Language, or Encoding. This is the strictest implementation with the fewest unexpected side effects, and is the default behavior.

To include extensions associated with Handlers and/or Filters, set the `MultiviewsMatch` directive to either `Handlers`, `Filters`, or both option keywords. If all other factors are equal, the smallest file will be served, e.g. in deciding between `index.html.cgi` of 500 bytes and `index.html.pl` of 1000 bytes, the `.cgi` file would win in this example. Users of `.asis` files might prefer to use the Handler option, if `.asis` files are associated with the `asis-handler`.

You may finally allow `Any` extensions to match, even if `mod_mime` doesn't recognize the extension. This can cause unpredictable results, such as serving .old or .bak files the webmaster never expected to be served.

For example, the following configuration will allow handlers and filters to participate in Multviews, but will exclude unknown files:

    MultiviewsMatch Handlers Filters

`MultiviewsMatch` is not allowed in a `<Location>` or `<LocationMatch>` section.

### See also

- `Options`
- `mod_negotiation`

## RemoveCharset Directive

Description: | Removes any character set associations for a set of file extensions
Syntax: | `RemoveCharset extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveCharset` directive removes any character set associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files.

The extension argument is case-insensitive and can be specified with or without a leading dot.

### Example

    RemoveCharset .html .shtml

## RemoveEncoding Directive

Description: | Removes any content encoding associations for a set of file extensions
Syntax: | `RemoveEncoding extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveEncoding` directive removes any encoding associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files. An example of its use might be:

### /foo/.htaccess:

    AddEncoding x-gzip .gz
    AddType text/plain .asc
    <Files "*.gz.asc">
        RemoveEncoding .gz
    </Files>

This will cause `foo.gz` to be marked as being encoded with the gzip method, but `foo.gz.asc` as an unencoded plaintext file.

### Note

`RemoveEncoding` directives are processed after any `AddEncoding` directives, so it is possible they may undo the effects of the latter if both occur within the same directory configuration.

The extension argument is case-insensitive and can be specified with or without a leading dot.

## RemoveHandler Directive

Description: | Removes any handler associations for a set of file extensions
Syntax: | `RemoveHandler extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveHandler` directive removes any handler associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files. An example of its use might be:

### /foo/.htaccess:

    AddHandler server-parsed .html

### /foo/bar/.htaccess:

    RemoveHandler .html

This has the effect of returning `.html` files in the `/foo/bar` directory to being treated as normal files, rather than as candidates for parsing (see the `mod_include` module).

The extension argument is case-insensitive and can be specified with or without a leading dot.

## RemoveInputFilter Directive

Description: | Removes any input filter associations for a set of file extensions
Syntax: | `RemoveInputFilter extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveInputFilter` directive removes any input filter associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files.

The extension argument is case-insensitive and can be specified with or without a leading dot.

### See also

- `AddInputFilter`
- `SetInputFilter`

## RemoveLanguage Directive

Description: | Removes any language associations for a set of file extensions
Syntax: | `RemoveLanguage extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveLanguage` directive removes any language associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files.

The extension argument is case-insensitive and can be specified with or without a leading dot.

## RemoveOutputFilter Directive

Description: | Removes any output filter associations for a set of file extensions
Syntax: | `RemoveOutputFilter extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveOutputFilter` directive removes any output filter associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files.

The extension argument is case-insensitive and can be specified with or without a leading dot.

### Example

    RemoveOutputFilter shtml

### See also

- `AddOutputFilter`

## RemoveType Directive

Description: | Removes any content type associations for a set of file extensions
Syntax: | `RemoveType extension [extension] ...`
Context: | virtual host, directory, .htaccess
Override: | FileInfo
Status: | Base
Module: | mod_mime

The `RemoveType` directive removes any media type associations for files with the given extensions. This allows `.htaccess` files in subdirectories to undo any associations inherited from parent directories or the server config files. An example of its use might be:

### /foo/.htaccess:

    RemoveType .cgi

This will remove any special handling of `.cgi` files in the `/foo/` directory and any beneath it, causing responses containing those files to omit the HTTP Content-Type header field.

### Note

`RemoveType` directives are processed after any `AddType` directives, so it is possible they may undo the effects of the latter if both occur within the same directory configuration.

The extension argument is case-insensitive and can be specified with or without a leading dot.

## TypesConfig Directive

Description: | The location of the `mime.types` file
Syntax: | `TypesConfig file-path`
Default: | `TypesConfig conf/mime.types`
Context: | server config
Status: | Base
Module: | mod_mime

The `TypesConfig` directive sets the location of the media types configuration file. File-path is relative to the `ServerRoot`. This file sets the default list of mappings from filename extensions to content types. Most administrators use the `mime.types` file provided by their OS, which associates common filename extensions with the official list of IANA registered media types maintained at http://www.iana.org/assignments/media-types/index.html as well as a large number of unofficial types. This simplifies the `httpd.conf` file by providing the majority of media-type definitions, and may be overridden by `AddType` directives as needed. You should not edit the `mime.types` file, because it may be replaced when you upgrade your server.

The file contains lines in the format of the arguments to an `AddType` directive:

`media-type [extension] ...`

The case of the extension does not matter. Blank lines, and lines beginning with a hash character (`#`) are ignored. Empty lines are there for completeness (of the mime.types file). Apache httpd can still determine these types with `mod_mime_magic`.

Please do not send requests to the Apache HTTP Server Project to add any new entries in the distributed `mime.types` file unless (1) they are already registered with IANA, and (2) they use widely accepted, non-conflicting filename extensions across platforms. `category/x-subtype` requests will be automatically rejected, as will any new two-letter extensions as they will likely conflict later with the already crowded language and character set namespace.

### See also

- `mod_mime_magic`