Code blocks in tinymce could sometimes end up exploded into the sub
elements of the codemirror display.
This changes the strategy to render codemirror within the shadow dom of
a custom element while preserving the normal pre/code DOM structure.
Still a little instability when moving/adding code blocks within details
blocks but much harder to break things now.
- Ensures padding works across FF & Chrome, was only working on FF
before.
- Fixes sketchy editor positioning focus on FF, since tinyMCE would
add a hidden element to the bottom of the body which would remove/add
our body padding causing unstable positioning.
Due to causing content images to be rendered in unexpected ways.
- Also removed CSS filters from other image usage.
- Tweaked header CSS filtering to not be so aggressive.
- Forced WYSIWYG editor to be on its own layer since that would allow
massive larger performance increases in Safari, especially when using
dark mode.
Closes#2045.
Closes#2154.
- Updated editor, and other area, styles to look okay in dark mode.
- Used tinyMCE theme generator to create dark mode theme.
- Updated tinymce to latest 4x version.
