Bugzilla

(In reply to Luke from comment #16)
> As an fyi, I've submitted a WebKit PR to address the vertical scrollbar space being incorrectly reserved. https://github.com/WebKit/WebKit/pull/13832

Thanks. For reference, this was https://bugs.webkit.org/show_bug.cgi?id=256697

> I'm happy to do a follow up WebKit PR if there's a change needed there (I believe there is) to address the horizontal scrollbar case.

This followup (more closely tied to the focus of this bug here) seems to be tracked in https://bugs.webkit.org/show_bug.cgi?id=256811 .

(In reply to Ian Kilpatrick [:iank] from comment #17)
> As a FYI Luke submitted the changes in Blink as - https://chromium-review.googlesource.com/c/chromium/src/+/4529815

Thanks. Looking at those changes, focusing on the horizontal scrollbar `overflow:auto` aspects -- it looks like in Blink, the `layout_box.cc` check for `overflow-wrap: normal` (from comment 11) is now disabled-by-default (behind the flag `RuntimeEnabledFeatures::LayoutNewTextAreaScrollbarEnabled`).

This means that (by default, unless this flag is toggled) Blink will render testcases 1 and 3 with the same textarea-heights, and testcases 2 and 4 with the same textarea heights -- not reserving height for a horizontal scrollbar in any of those cases.

So: per comment 15, I'll put my (to-be-added) `overflow-wrap` check behind an off-by-default pref for consistency with the behavior that now exists in Blink.  Hopefully we never need the `overflow-wrap` check, but we can fall back on it via a pref flip if it ends up being necessary.

(In reply to Luke from comment #16)
> As an fyi, I've submitted a WebKit PR to address the vertical scrollbar space being incorrectly reserved. https://github.com/WebKit/WebKit/pull/13832

Thanks. For reference, this was https://bugs.webkit.org/show_bug.cgi?id=256697

> I'm happy to do a follow up WebKit PR if there's a change needed there (I believe there is) to address the horizontal scrollbar case.

This followup (more closely tied to the focus of this bug here) seems to be tracked in https://bugs.webkit.org/show_bug.cgi?id=256811 .

(In reply to Ian Kilpatrick [:iank] from comment #17)
> As a FYI Luke submitted the changes in Blink as - https://chromium-review.googlesource.com/c/chromium/src/+/4529815

Thanks. Looking at those changes, focusing on the horizontal scrollbar `overflow:auto` aspects -- it looks like in Blink, the `layout_box.cc` check for `overflow-wrap: normal` (from comment 11) is now disabled-by-default (behind the flag `RuntimeEnabledFeatures::LayoutNewTextAreaScrollbarEnabled`).

This means that (by default, unless this flag is toggled) Blink will render testcases 1 and 3 with the same textarea-heights, and testcases 2 and 4 with the same textarea heights -- not reserving height for a horizontal scrollbar in any of those cases.

So, amending the plan from comment 15: I'll put my (to-be-added) `overflow-wrap` check behind an off-by-default pref for consistency with the behavior that now exists in Blink.  Hopefully we never need the `overflow-wrap` check, but we can fall back on it via a pref flip if it ends up being necessary.