User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:83.0) Gecko/20100101 Firefox/83.0

Steps to reproduce:

1. make sure your Fission is active! (fission.autostart=true)
2. create an iframe in the popup with some filter style, for example:

<iframe src="http://benchmark.fastaddons.com/" style="filter: grayscale(50%)"></iframe>

I've prepared extension in attachment, so just load it and click the popup icon.

Actual results:

iframes with filter style won't load (or are not visible).

Expected results:

Filter should work on iframe in popup, it works when loaded into a tab, only in popup it's broken

Thanks for the test case, Juraj!

Nika can reproduce the bug with the test case.

kmag will investigate and then probably delegate to someone on the Graphics team.

Presumably this is due to bug 1559251, it's an issue on non-WebRender. And unfortunately we don't (yet) enable WebRender in popup windows.

This is a Graphics issue and I'm hoping someone in the Graphics team can debug and work on this issue using the clear STR in this bug.

Hey Neha, this is non-webrender issue. Does the fission team care about this then?

Actually, never mind.

We should probably be using software webrender for those windows.

We're thinking sw-wr for popups will fix this.

I tried enabling hardware webrender on those windows they failed to have transparency

https://searchfox.org/mozilla-central/search?q=WidgetTypeSupportsAcceleration&redirect=false

We'll need bug 1687124 fixed to get proper transparency.

If this is only for (iframes, in a popup, with a css filter), it can probably be M7.

Should be fixed by bug 1688096.

I see bug 1688096 is fixed, so should this be now fixed in Nightly 88.0a1 (2021-02-26)? Because I can still reproduce the issue.
Also I've noticed my Developer Edition is now affected as well, seems like the Fission got activated.

I'm using filter style to implement dark mode in my Web Translate addon, so this bug breaks it completely. Should I start looking for a different solution or is this gonna be fixed before it reaches Release channel? I don't know what M7 means.

Jim, the reporter says this is still reproducible with Fission. Can someone from Graphics team look into this?

juraj.masiar , Fission is now available to be enabled via the pref in Beta and Release (via Bug 1674871) so that's why you are able to observe the effect in your dev edition version too. You can turn Fission on/off using fission.autostart pref followed by a restart.

We are hoping to finish Fission M7 work in Fx88, which goes to Beta on March 22 and to Release on April 20. https://wiki.mozilla.org/Release_Management/Calendar has all the branch release dates for your reference.

This is fixed, however the new feature is behind a pref at the moment - gfx.webrender.software.unaccelerated-widget.allow

Was the software WebRender disabled again for popups?
Because this bug reapers for me in the current Beta 89.0b13.