Make more and nextpage tags beautiful (pure CSS) and translatable by converting them to wpviews

[iseulde]

Patch includes patch for #28533 to make it work.

Now they also display well against all kinds of backgrounds, and no visible pixels when you zoom in.

[iseulde]

Added after and before screenshots with exactly the same content and theme.

[iseulde]

The color for the dashed borders depends on the color of the body's color rule.

[iseulde]

I wish we had a __() function in JS. :) We should probably split mce-view.js before localising it...

[azaozz]

Not sure converting to wpViews is the best thing for these. Changing the placeholders from <img> to <hr> seems better. Then we can still use "more advanced" CSS, but keep things simple.

[afercia]

Replying to azaozz:

Changing the placeholders from <img> to <hr> seems better. Then we can still use "more advanced" CSS, but keep things simple.

I'm playing a bit with this and tried many things, including <hr> and <table>, but I always end up with something a bit hacky and not so future-proof.
Mr. Ozz, any objections to use ​TinyMCE noneditable plugin? Looks like it handles selection, caret position, dragging, delete, backspace and it would allow to use a normal inline element + CSS generated content instead of a void or replaced element where generated content is not guaranteed to work.

[iseulde]

#28539 was marked as a duplicate.

[iseulde]

I forgot we still had this ticket. Let's use #29804 now.