Post Editor doesn't reflect justification on the Post Content block

[jameskoster]

With #44065 merged it's possible for Post Content layout to be inherently more expressive.

Here's my single template:

Notice how all blocks within the post content are left-justified. This is accurately reflected in the Site Editor:

However, in the Post Editor everything remains centrally aligned:

It would be nice to fix this so that the Post Editor gives a more accurate portrayal of the frontend.

cc @andrewserong

[andrewserong]

Thanks for writing up this issue and including the screenshots @jameskoster! The fix for this will likely also be a fix for #42911, so we may want to consolidate the issues.

[andrewserong]

Just closing this one out now, too, since it's resolved as of #44258. Thanks @tellthemachines!