On IRC Andreia pointed out the case when a Control is part of the pending
validation chain, and then this Control is removed. So the attached codes
adds the check to look for any control (or children) that could be int the
pending validation chain, and thus need to be removed (this is what .Net
So I found that on linux the standard clipboard behavior isn't there.
I select text with the mouse, it's not on the clipboard. So I tried
this:
RichTextBox txt = new RichTextBox();
txt.SelectionChanged += delegate (object o, EventArgs a) {
if (txt.SelectedText != String.Empty) {
