Rated 4 out of 5 stars
It's really great, I like TextMarker very much.
However, since I use "Search for text when start typing" option in Firefox, it's impossible for me to use "use keyboard shortcut" (using M, B N key) in TextMarker - which is a very great option.
Therefore I would suggest TextMarker to give user the option to customize their own keys. (as for me I prefer F1, F2 key).
Generally, a great add-on.