Enable TinyMCE for attachment descriptions

[SergeyBiryukov]

Enabling TinyMCE for attachment descriptions was briefly mentioned in #24472, but it seems like it was never really discussed as a default option before.

[23083] introduced the current text editor with quick tags, before that it was just a simple textarea.

[28944] introduced the wp_editor_settings filter, so it should be possible to override 'tinymce' => false on the attachment editor instance.

Any reasons not to enable it by default?

[desrosj]

@SergeyBiryukov did you have any use cases in mind?

Talked this over in the media bug scrub today with @joemcgill. Are there any locations where the description is being sanitized and would cause something to break when HTML is included?

It is also a poor user experience that the attachment edit screen supports this (​https://cloudup.com/c9dhHFtzLtl+) but the modal does not (​https://cloudup.com/cT4IGkRXoEm+).

[SergeyBiryukov]

Replying to desrosj:

@SergeyBiryukov did you have any use cases in mind?

Must be a project I worked on or a support topic I answered at the time, but I could not find any additional details.

Talked this over in the media bug scrub today with @joemcgill. Are there any locations where the description is being sanitized and would cause something to break when HTML is included?

The field already has an HTML editor since [23083], it's just that quicktags.js is not as convenient as TinyMCE :)