With bug 1654454 we have support for WebDriver:FindElement, and WebDriver:FindElements. It means we can port WebDriver:SwitchToFrame over to the JSWindowActor implementation.

Depends on D84707

Because our element store is still in the content process, existing tests will start failing because not only each frame gets it's own store but also each navigated page because new actors are getting spawned. As such bug 1654513 is needed to get it fixed.

Maja, I wonder if we want to get it landed anyway even with the known caveat from above. What do you think? Happy to also discuss in a meeting.

Fine with landing it. We should keep track of tests that are expected to fail wherever possible (based on the marionette.fission.enable pref). Unfortunately, wpt doesn't allow to set expectation conditional on a pref.

Another option would be to delay landing the second patch and simply accept that all tests regarding frame switching will fail. It should be easier to disable wdspec tests based on that.

I turns out that delaying the landing of the second patch will cause even more problems given that more tests exist that make use of the WebDriver:switchTo(Parent)Frame command, so all other commands will fail compared to only the element affected ones. I suggest we just land both now and have the element store patch for parent ready soon. Note, that we still have everything behind a pref, so nothing in CI will be affected for now.

https://hg.mozilla.org/mozilla-central/rev/0883c2b689df
https://hg.mozilla.org/mozilla-central/rev/627409e8dc76