> capture selections or right-click (think: WYSIWYG editor widget)
Why, no, not the same.
I think it is ok for a webapp to be aware that I selected some text, and which text, so a further click on "boldface" would have a context.
But it is not ok for a webapp to interfere with the text selection itself.
For instance, well-intentionned chrome always add "http:// when I select the url. It gets in my way very often and it is not what I intended: I did select google.com with my mouse very carefully, I do not want Chrome to be clever and add "http://. By the way, this issues comes from the excessively minimal UI: Chrome should not hide "http:// in the url bar, point-barre.
I do not use Evernote because it messes with my selections.
I have to use Trello at work but this bully don't even let me select a card title.
And the list goes...