Enable spell checking in 'plain text' mode

[pavelkostyurin]

Built-in Chrome Spellchecker works when page is edited in 'rich text' mode.
Although I can't figure out why it doesn't work in default, 'plain text' mode.

Any help would be appreciated!

[pavelkostyurin]

Seems like it requires a newer / customized version of CodeMirror which is used for 'plain text' mode.
https://stackoverflow.com/questions/12343922/codemirror-with-spell-checker

[tcnh]

did some quick testing with my bootstrap-plus theme (as it overwrites fitnesse's default codemirror version with codemirror 5.52).
It's pretty trivial to enable it there, but it makes my pages look pretty red in edit mode. So I'd like to add a toggle to enable/disable the browser's built-in spellcheck.

To get this in vanilla fitnesse requires some more work (I don't know if upgrading might break rich text editor; as I removed that from my theme)