Mozilla91 v10.
Containing patches for linux, windows, macos builds. I can also make separate merge requests if we want to merge linux, windows and macos separately.
Closes #40347 (closed), #40044 (closed), #40222 (closed), #40305 (closed), #40306 (closed), #40307 (closed), #40357 (closed), #40048 (closed), #28240 (closed), #40334 (closed), #40048 (closed), #40360 (closed).
Replacing !346 (closed).
/cc @gk