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diff --git a/chromium/docs/website/site/updates/ua-ch/index.md b/chromium/docs/website/site/updates/ua-ch/index.md deleted file mode 100644 index 1c048310e6a..00000000000 --- a/chromium/docs/website/site/updates/ua-ch/index.md +++ /dev/null @@ -1,95 +0,0 @@ ---- -breadcrumbs: -- - /updates - - updates -page_name: ua-ch -title: User-Agent Client-Hints ---- - -# **Overview** - -This page provides a central reference point about the User-Agent Client Hints -(UA-CH) rollout for Chrome 85+ stable. If you’re not familiar with User-Agent -Client Hints, you can read up on them -[here](https://web.dev/user-agent-client-hints/). - -# **Launch Timeline** - -Last updated November 22, 2021 - -* **March 3, 2021: UA-CH is rolling out to 100% of stable population - in tandem with version 89** -* **October 14, 2020:** We've paused increasing the population subset - of the roll out while we examine ecosystem impact and investigate - possible issues due to the Structured Headers format. -* **October 5, 2020:** Gradual roll out continues to a larger subset - of the population. -* **September 9, 2020:** UA-CH will begin roll out to an initial small - percentage of the Chrome 85 stable population. -* **May, 2020:** UA-CH was rolled out to most of Chrome Canary, Dev - and Beta populations. -* **June 10, 2021**: Critical-CH and ACCEPT_CH features were disabled - due to a potential crash while investigating and implementing fixes. -* **November 22, 2021**: Intent to Ship: Sec-CH-UA-Full-Version-List - user-agent client hint. - -# **Possible Site Compatibility Issue** - -UA-CH is an additive feature, which adds two new request headers that are sent -by default: \`sec-ch-ua\` and \`sec-ch-ua-mobile\`. Those request headers are -based off of [Structured Field -Values](https://httpwg.org/http-extensions/draft-ietf-httpbis-header-structure.html), -an emerging standard related to HTTP header values. They contain characters -that, though permitted in the HTTP specification, weren’t previously common in -request headers, such as double-quotes (“), equal signs (=), forward-slashes -(/), and question marks (?). Some Web-Application-Firewall (WAF) software, as -well as backend security measures, may -[mis-categorize](https://bugs.chromium.org/p/chromium/issues/detail?id=1091285) -those new characters as “suspicious”, and as such, block those requests. - -This typically presents itself as a 4XX HTTP response code (e.g. 400, 404 or -422), either on any request or on POST requests or API endpoints (which servers -tend to take special precautions with). - -# **How to file bugs** - -Here are some basic troubleshooting steps: - -* Check `chrome://version` and make sure the version number is at - least 85. The UA-CH feature is only enabled for Chrome 85+. -* If the issue is primarily the browser or tab experiencing a crash or - hang, it is not likely to be a UA-CH related issue. -* Test again with the \``--disable-features=UserAgentClientHint`\` - command line flag. You can use the [test - site](https://user-agent-client-hints.glitch.me/) to verify that the - feature is indeed off. -* If the problem persists, the source of the issue is likely to be - elsewhere. -* In case the problem went away, that’s a strong indicator that it is - a UA-CH related issue - -If after trying these things, you have determined that it may be a UA-CH issue, -please [file a CR bug](https://crbug.com/new), including \[UA-CH\] in its title. -Add a comment about it to the following [tracking -bug](https://bugs.chromium.org/p/chromium/issues/detail?id=1091285). - -# **(Deprecated) How to identify if a user is in the stable experiment** - -**Note:** As of Chrome 89, this feature is rolled out to full population. - -Go to `chrome://version?show-variations-cmd`. Search for “UserAgentClientHint” -in the long command string towards the bottom. If they are in the enabled group, -the `--force-fieldtrials` value will say something like one of the following: - -* /\*UserAgentClientHintRollout/Enabled/ -* /\*UserAgentClientHintRollout/Enabled_v2/ -* /\*UserAgentClientHintRollout/Enabled_v3/ -* /\*UserAgentClientHintRollout/Enabled_v4/ -* /\*UserAgentClientHintRollout/Enabled_v5/ - -If they do not have the features enabled, the string will be absent. - -Alternatively, going to this [test -site](https://user-agent-client-hints.glitch.me/) can confirm the feature is -enabled - when the feature is enabled \`sec-ch-ua\` and \`sec-ch-ua-mobile\` -requests will be listed as being sent by the client.
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