Multi-line block comments break when scrollbars should appear on Safari

cpcallen commented 5 months ago

Check for duplicates

[ ] I have searched for similar issues before opening a new one.

Description

In Safari 17.4.1 on macOS 13.6.6, when a multi-line block comment exceeds the height of the textarea, the textarea completely disappears.

Reproduction steps

Load the playground in Safari.
Add a block (e.g. controls_if) to the workspace.
Right click on the block and choose "add comment"
Click on question-mark icon to open block comment bubble.
Type "blah" and press enter. Repeat until text is too tall for textarea.

Observe that, unlike on Chrome where a vertical scrollbar appears, on Safari yellow textarea instead completely disappears, leaving only the empty bubble.
Observe that zooming the workspace may cause the area that should be text-on-yellow to instead be a blank white rectangle.
Observe that scrolling the workspace so that the bubble is in the upper-left corner of the viewable area may cause part of the white rectangle or blank bubble to show a blank yellow rectangle instead, with the lower-right corner of the yellow rectangle seeming to be pinned to a particular fixed coordinate on the page.

Stack trace

No response

Screenshots

Note screenshots display an unrelated text positioning bug that was caused by #8158. This bug was not caused by #8158 and can be observed at commit 36b7569.

Browsers

No response

cpcallen commented 5 months ago

@maribethb reports she was able to reproduce.

I can reproduce in v10.4.3, so it is not a regression in v11.

NeilFraser commented 5 months ago

This is reproducible in Blockly Games which uses a version of Blockly that's several years old. There is absolutely no way that this bug could have lurked undetected for so long. Thus the logical conclusion is that this is a recent regression in Safari.

Also, I can now reproduce it on my computer. The key is that System Settings > Appearance > Scrollbars should be set to "When scrolling" to trigger the bug. If Scrollbars are set to "Always" then the bug doesn't manifest.

This is 100% a bug in Safari itself (or OS X).

NeilFraser commented 5 months ago

Created a minimal testcase and filed a bug with Webkit: https://bugs.webkit.org/show_bug.cgi?id=274408

BeksOmega commented 5 months ago

Closing since this isn't our bug.

cpcallen commented 2 months ago

Reopening this until it gets fixed in Safari so we don't get further duplicate reports.

google / blockly