Editor: Justify text option not working on Simple Sites

[susanjanec]

Steps to reproduce

1. Starting at URL: https://susanjanewptestsite12345.blog/2019/08/26/a-sticky-post-example/
2. Applied the Justify option to all paragraphs
3. Published the post and viewed the post and not seeing the text is justified
4. CSS class on all paragraphs showing as has-text-align-justify to confirm the justify option was applied.

What I expected

Text will appear as justified.

What happened instead

Text did not justify

Browser / OS version

Chrome Version 76.0.3809.132 / macOS High Sierra Version 10.13.6

Screenshot / Video

https://cld.wthms.co/s6UEA7

Context / Source

User came into chat regarding this issue - provided CSS as a workaround for now.

[mikeicode]

Another in 15020826-hc (the class is added to the text but not applied).

This appears to be related to the 6.5 release since this occurs on Simple sites but not on AT sites (which aren't at 6.5 yet).

[detlefholtz]

Got another in 15179400-hc.

All of the posts that the user's written in the last month aren't justifying correctly, so I sent them the CSS, which did the trick.

Unfortunately, their galleries are also not showing correctly. The images are aligned vertically instead of horizontally. Editing the galleries via the editor fixes them, but they have many galleries and have to do this manually.

[kwight]

@detlefholtz can you open a separate issue for the galleries please, thanks!

[kwight]

Ah, it turns out this has been broken since Gutenberg 6.3 (but we've been on 6.2 until skipping to 6.5 yesterday).

It's due to this change; I'll update our plugin to use the new class format.

[kwight]

D33289-code is ready for review; this will likely go out this coming Monday.

[darnelldibbles-zz]

A few reports in forums on this today - posting here so that we can notify them once things are back up and running:
https://en.forums.wordpress.com/topic/justify-function-not-working/
https://en.forums.wordpress.com/topic/justify-paragraphs/#post-3373241

[macmanx2]

Also reported at https://en.forums.wordpress.com/topic/jusify-text/

[kosiew]

another case here #2384169-zen

[liviopv]

Another report: #2383730-zen

[carinapilar]

Another report: #2384453-zen. User doesn't have the CSS option to use the workaround.

[CoachBirgit]

Another report: #2384515-zen (German upwork). User doesn't have the CSS option to use the workaround.

[tijosh]

Another report in #2384693-zen

[sourourn]

Another one here: #2382364-zen

[sophiegyo]

With regards to the report from #2383564-zen, it looks like paragraphs using drop caps don't actually get the justify class, even if the justify alignment is selected in the editor.

[sophiegyo]

Another report: #2386304-zen

[mlaetitia]

Another report: #2383722-zen
User doesn't have the CSS option to use the workaround.

[Agepeuve]

Also reported here: https://es.forums.wordpress.com/topic/justificar-el-texto/

[Agepeuve]

And here: #2388190-zen

[kylemcph]

Another report here: #14892362-hc

Sent CSS workaround.

[sourourn]

Another one: #2388362-zen

[catkit]

Chat: #15603626-hc