I see that Checkboxes in Rich Text docs have been dicussed here before, because they are such a great tool in ToDo lists.
DevonThink already has an Insert Bullet command under the Edit menu. I like the Insert Checkbox in MacJournal’s Edit menu – very useful.
Now I’m using emoji ( 
) under the Special Characters, but this could definitely be improved upon with a real checkbox.
Thanks for listening.
Option V = √ if you don’t need the box itself. 
I agree with ahmyo in that Checkboxes are such a great tool for ToDO lists. While discussed here more than once in the past the feature request has not been implemented.
The functionality difference between an emoticon or Option V = √ and a checkbox is quite different.
Having the checkbox, although a small addition in itself, would enhance Devonthink considerably with the new functionality it brings. I hope that this feature request can be reconsidered for inclusion.
Thanks.
Why is edit insert CHECKBOX in a rich text file Still not working??
The Insert>Checkbox command does work, but it is for formatted note documents only which is why it is dimmed in rich text documents.
From the manual:
Inserting a checkbox is not part of the base RTF text-engine we use. (You will note isn’t not present in TextEdit.)
And remember, there are a great many things to tend to. and priorities must be maintained.