I rage quit websites when they put nasty tasks on me. Task such as filling a long form with super weird 'validation' rules or losing filled fields when accidentally reloading or even worse losing filled fields when I took too much time to fill and my session expired.
I fight back websites which disable the right click context menu and use plugins which overwrite such stupid nonsense or simply never come back (I'm looking at you Google Docs). Selecting text and look up for its definition or query a search of text is essential to me. On some table based websites, I need to copy entire columns but not the whole table.

My biggest point here on the list is about that false security mechanism called security questions. When I've lost my password and some silly security questions asking me about my dad's first pet name or when my mother first time kissed my father - to justify that I am I. I could handle such stupid false shitty behaviors if I could define the question by myself. But more and more websites took that decision away from me and forced me to answer predefined easy to social engineer questions. I feel more and more site helping the NSA. With easy security questions, no one needs to crack encrypted connections or passwords. Just lookup some Facebook pages or other social media and you know pretty much anything about anyone's secret questions/answers.