ksnip
Open text edit mode when double-click on textbox figure in Text tool
It isn't easy to understand how to edit already typed text when "Text" tool is selected. Will be good to make it better via auto opening text edit mode when user do a double-click on textbox figure, instead of placing new textbox figure.
Also will be good to auto-clean empty text figures (with zero width and empty string), which can be created too many via simple clicks when users forgot switch to Select tool from Text and try to select something.
The problem is not as simple as you might think, a double click is at first a click and a click creates an item, then you detect the second click you would need to go back and remove the just created item which is already in the undo stack. Can be programmed but with some ugly code. Other Applications switch to select tool after drawing an item, in this case it's easy to work with the double click, this can now be done with the annotator too but getting both might be tricky.
The solution for double-click interception can be adding timeout after first single click, that will wait if second click happens, and if no - execute single-click action. This can be done always, or only when clicked under already exists text object.
Or solution, inspired by Inskcape, is always treat clicks under already exists text object as edits of previous object, instead of creating new object, maybe even this will be better for users.
The first proposal is IMHO not a good solution, it would add delay for normal item adding which is probably the most often use case.
The second might be a possible solution but is going to prevent drawing items over items or forces you to start drawing on an empty area and move it over the next item. I think we should bring this to the discussion board and get some option from other users.
Can you please test again, the Text Annotation Tool has been reimplemented.