Twenty Fifteen: Separator block is too thick in the iframe editor

[nidhidhandhukiya]

Steps to reproduce the issue :-

1. Activate Twenty Fifteen theme.
2. Choose separator block.
3. Now see editor and front side.

You can able to see both the side block looks different.
I have attached video for better understanding.
Video URL :- ​https://share.cleanshot.com/nLtGwVmQWnDrHBvCZPV3

[darshitrajyaguru97]

Patch report for https://core.trac.wordpress.org/attachment/ticket/60079/60079.patch

Environment:
===========
WordPress: 6.4.2
PHP: 8.1.9
Web Server: Nginx
Browser: Chrome
OS: Windows 10

Screenshots:
===========
Before Patch:
Backend: ​https://prnt.sc/devt5LHX4RL7
Frontend: ​https://prnt.sc/xROKGfLbplYU

After Patch:
Backend: ​https://prnt.sc/devt5LHX4RL7
Frontend: ​https://prnt.sc/vLAV8NQpQbza

After Applying the patch it's working properly.

[sabernhardt]

sets border to zero in editor-blocks.css and corrects the typo on "Separator"

[sabernhardt]

The problem is in the iframe editor, not the front end. Separator blocks (and other hr elements) are intended to be thin in this theme.

Without the iframe, the editor added .editor-styles-wrapper to hr for styles from the Classic editor stylesheet, which would override the ​block's opt-in styles. Now the discrepancy between blocks.css and editor-blocks.css since [43798] can result in the 2-pixel bottom border (the original blocks stylesheet set border: 0 but editor-blocks did not).

On the other hand, the light color makes the separator almost imperceptible in the editor because the iframe pulls in wp-admin/css/common.css with its off-white background color on body. The mismatch does not bother me much when the extra-thick line is slightly easier to see and to click.

[yuvrajsinh2211]

Testing of patch: https://core.trac.wordpress.org/attachment/ticket/60079/60079.patch

Tested in the below environment:

PHP: 8.1.9
WordPress: 6.4
Theme: Twenty Fifteen
Browser: Chrome
Plugin: No plugins

---

Before Patch Screenshots:
Backend: ​https://prnt.sc/g9pRxD1ZOfzl
Frontend: ​https://prnt.sc/btCAh6CWy7V7

---

After Patch Screenshots:
Backend: ​https://prnt.sc/rD-bmLusWsSC
Frontend: ​https://prnt.sc/wxBdO_4-bhnB

As tested, Patch is working fine.

[sabernhardt]

refreshed patch after [57300]

[sabernhardt]

sets border to zero in editor-blocks.css

[karmatosed]

This has testing and looks like a candidate to me to move to this release. I am going to do that but if anyone has objections let me know.

Next steps are to test to be sure as it has sat for a few weeks and then move to commit.

[karmatosed]

In 58231:

Twenty Fifteen: Resolves seperator block being too thick in iframe editor.

The seperator block was looking different in the iframe editor. This resolves that by unifying.

Props nidhidhandhukiya, sabernhardt, darshitrajyaguru97, yuvrajsinj2211.
Fixes #60079.

[karmatosed]

I tested this so moved it to commit, thank you everyone.