Developer reply by C-E
Rated 4 out of 5 stars
Works, but controls are a bit obtuse, having to read instructions to learn to use the correct combination of mouse clicks and Ctrl/Shift keys to make it work. Having a drop-down menu option for the Mark button to set/unset colours and access a help screen would make it easier. (There was a highlighter add-on for Mozilla SeaMonkey Messenger that worked much this way.) Gmail has the highlighter feature now inbuilt; Thunderbird should consider doing so, too.
This review is for a previous version of the add-on (5.1.0).Currently it is not possible to set up a drop-down menu for the Mark button. (See also https://thunderbird.topicbox.com/groups/addons/T3bbe7dd7c1833dcb/drop-down-menu-option-for-composeaction-button). Maybe it will be possible in Thunderbird version 90+. This said, would you reconsider the rating for my Add-on?
I agree that Thunderbird should implement highlighting as standard feature and make my Add-on superfluous.
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