What is the problem?

On versions of Chrome between 90 and 97 (inclusive), the request to /checkuser/v0/useragent-clienthints/revision/ returns:

{"errorKey":"rest-missing-body-field","messageTranslation:{"en":"Mandatory field \"brands\" missing from request body"} ... }

(or alternatively ...\"fullVersionList\" missing...)

These versions of Chrome do support client hints, but are missing fields we mark as required. We could perhaps make those fields optional.

Versions 90-92 are missing the brands field.

Versions 93-97 are missing the fullVersionList field.

This also affects Edge and Opera (as they both are based on Chrome).

Steps to reproduce problem

1. On a wiki with CheckUser installed and $wgCheckUserClientHintsEnabled = true (which is the default)
   1. Installing on docker
   2. Create one on https://patchdemo.wmflabs.org/ (You could try this exist one https://patchdemo.wmflabs.org/wikis/c7fc0fc3e1/wiki/Main_Page if it is still up)
2. On any Chrome/Edge version 90-97 (or a version of Opera based on those versions of Chrome)
3. Open devtools
4. Make an edit (via Source Editor, Visual Editor or Discussion Tools)
5. In devtools network tab, you should see a request to <server>/w/rest.php/checkuser/v0/useragent-clienthints/revision/<revid>

Expected behavior: Request returns 200
Observed behavior: Request returns 400

Environment

Browser: Tested on various versions of Chrome, Edge and Opera (on an emulated version of Windows 11).
Wiki(s): CheckUser 2.5 (93ada3d) 14:18, 25 July 2023.