This type is a string, which represents the context in which a resource was fetched in a web request.
It's used to filter the requests you listen to using the webRequest API. For example: you can listen to requests only for images, or only for scripts.
Values of this type are strings. Possible values are:
beacon
Requests sent through the Beacon API.
csp_report
Requests sent to the report-uri given in the Content-Security-Policy header, when an attempt to violate the policy is detected.
font
Web fonts loaded for a @font-face CSS rule.
image
Resources loaded to be rendered as image, except for imageset on browsers that support that type (see browser compatibility below).
imageset
Images loaded by a <picture> element or given in an <img> element's srcset attribute.
main_frame
Top-level documents loaded into a tab.
media
object
Resources loaded by an <object> or <embed> element.
Browsers that don't have a dedicated object_subrequest type (see browser compatibility below), also label subsequent requests sent by the plugin as object.
object_subrequest
Requests sent by plugins.
ping
Requests sent to the URL given in a hyperlink's ping attribute, when the hyperlink is followed.
Browsers that don't have a dedicated beacon type (see browser compatibility below), also label requests sent through the Beacon API as ping.
script
Code that is loaded to be executed by a <script> element or running in a Worker.
speculative
In a speculative connection, the browser has determined that a request to a URI may be coming soon, so it starts a TCP and/or TLS handshake immediately, so it is ready more quickly when the resource is actually requested. Note that this type of connection does not provide valid tab information, so request details such as tabId, frameId, parentFrameId, etc. are inaccurate.
stylesheet
CSS stylesheets loaded to describe the representation of a document.
sub_frame
web_manifest
Web App Manifests loaded for websites that can be installed to the homescreen.
websocket
Requests initiating a connection to a server through the WebSocket API.
xml_dtd
DTDs loaded for an XML document.
xmlhttprequest
Requests sent by an XMLHttpRequest object or through the Fetch API.
xslt
XSLT stylesheets loaded for transforming an XML document.
other
Resources that aren't covered by any other available type.
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
ResourceType |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
beacon |
No | No | 45 | ? | No | No | ? | ? | 48 | ? | No | ? |
csp_report |
58 | 79 | 45 | ? | 45 | No | ? | ? | 48 | ? | No | ? |
font |
49 | 79 | 45 | ? | 36 | No | ? | ? | 48 | ? | No | ? |
image |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
imageset |
No | No | 45 | ? | No | No | ? | ? | 48 | ? | No | ? |
main_frame |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
media |
58 | 79 | 45 | ? | 45 | No | ? | ? | 48 | ? | No | ? |
object |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
object_subrequest |
No | No |
55Requests have been reported asobject_subrequest before, but the type was missing in the ResourceType object before Firefox 55.
|
? | No | No | ? | ? |
55Requests have been reported asobject_subrequest before, but the type was missing in the ResourceType object before Firefox 55.
|
? | No | ? |
other |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
ping |
49Requests sent bynavigator.sendBeacon(), and CSP reports in Chrome 49-57 (Opera 36-44), are also labeled as ping.
|
79 | 45 | ? |
36Requests sent bynavigator.sendBeacon(), and CSP reports in Chrome 49-57 (Opera 36-44), are also labeled as ping.
|
No | ? | ? | 48 | ? | No | ? |
script |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
speculative |
No | No | 63 | ? | No | No | ? | ? | 63 | ? | No | ? |
stylesheet |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
sub_frame |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
web_manifest |
No | No | 45 | ? | No | No | ? | ? | 48 | ? | No | ? |
websocket |
58 | 79 | 45 | ? | 45 | No | ? | ? | 48 | ? | No | ? |
xml_dtd |
No | No | 45 | ? | No | No | ? | ? | 48 | ? | No | ? |
xmlhttprequest |
44 | 79 | 45 | ? | 31 | No | ? | ? | 48 | ? | No | ? |
xslt |
No | No | 45 | ? | No | No | ? | ? | 48 | ? | No | ? |
Note: This API is based on Chromium's chrome.webRequest API. This documentation is derived from web_request.json in the Chromium code.
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webRequest/ResourceType