1820280 - Expose scrollbar-inline-size to Thunderbird's privileged about pages

Status: RESOLVED FIXED

(Core :: Layout: Scrolling and Overflow, enhancement)

Description

[Alessandro Castellani [:aleca]]

With bug 1812868, a new env(scrollbar-inline-size) was introduced which allows using the size of the overlay scrollbar as CSS value.
Unfortunately this variable is only exposed to chrome documents.
It would be very helpful to be able to use it inside Thunderbird's content documents, like about3Pane or aboutAddressBook, to add needed padding to our new TreeView widget.

Opening this RFE and pinging Emilio per this conversation.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1820280 - Be consistent for which URIs we expose chrome rules. r=#layout

Comment 2

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1820280 - Enable chrome rules in Thunderbird's about:3pane. r=#layout,aleca

For now a static list of URIs is probably fine. I asked Nika / Gijs if
we can do something better in any case.

We already have tests for stuff not getting exposed to content.

Depends on D171640

Comment 3

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1820280 - Don't proxy some principal destruction to the main thread. r=#layout

Drive-by, but nsIPrincipal is thread-safe now.

Depends on D171641

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1820280 - Expose chrome CSS to about: pages except srcdoc/blank. r=nika!

I believe these are the only two special-cases.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f8d2da589860
Be consistent for which URIs we expose chrome rules. r=dshin

Comment 6

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/f8d2da589860

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/88a386b2c591
Don't proxy some principal destruction to the main thread. r=dshin

Comment 8

[Cristina Horotan [:chorotan]]

https://hg.mozilla.org/mozilla-central/rev/88a386b2c591

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/cbe07218f8a2
Enable chrome rules in Thunderbird's about:3pane. r=aleca,dholbert

Comment 10

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/cbe07218f8a2

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/26f20f08170e
Expose chrome CSS to about: pages except srcdoc/blank. r=necko-reviewers,valentin,smaug

Comment 12

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/26f20f08170e