Bug 4808 – Line breaking behavior inconsistent between the Latin-1 and Unicode codepaths

• Component: Layout and Rendering
• Status: RESOLVED CONFIGURATION CHANGED

Summary: WebKit allows lines to break near non-Latin-1 characters where it does not allow the same 
break to occur if the character is Latin-1.

To reproduce: open the testcase in Safari.

Expected: the text in each of the table cells to break into 3 lines, the breaks being after "qui" and before 
"quia". Firefox renders as expected.

Actual: a line break occurs before "+", "(" and "$" when they come after non-Latin-1 (in the 3rd and 4th 
rows) and after ")" when it comes before non-Latin-1 (in the 2nd and 4th rows).

Created attachment 3722 [details]
testcase

[Alexey Proskuryakov]

I'm using Safari 1.3 (v312) right now, and the test case looks fine. This makes it a regression, I guess.

[Oliver Hunt]

It isn't a regression from v412, but i can't help wondering whether the break behaviour is correct, i'll 
confirm on the basis it's inconsistent with what is expected.  We need a font-type person to say what the 
correct behaviour should be.

[Jungshik Shin]

ref : UAX #14 : Line breaking properties (http://www.unicode.org/reports/tr14/) 

Firefox(2) is not compliant to that either. See, for instance, https://bugzilla.mozilla.org/show_bug.cgi?id=255990

[Alexey Proskuryakov]

*** Bug 14906 has been marked as a duplicate of this bug. ***

[Eric Seidel (no email)]

All cases look right in your test case Mitz.  Would you like to land the test case, or should we just close this?

[Ahmad Saleem]

Created attachment 461181 [details]
Safari 15.6 matches with other browsers

I am unable to reproduce this bug in Safari 15.6 on macOS 12.5 using attached test case and as can be seen from attached test case, Safari breaks the text same as other browsers.

I think this can be marked as "RESOLVED CONFIGURATION CHANGED". Thanks!

[zalan]

Thank you!