A X window system has an amazing feature called selection buffer:
This buffer is updated automatically when you select any text, and is generally the handiest buffer to use, as you can paste from it by clicking the middle mouse button at the required destination. I.E. by clicking the scroll button, or if you only have 2 mouse buttons you can click both simultaneously to emulate the middle mouse button.
I use it everyday wherever I can. In aha.io I get the following message when I try do it:
Please use Ctrl+V/Cmd+V keyboard shortcuts to paste contents.
It's extremely annoying. I need that selection buffer!
As described, we currently support Ctrl+V/Cmd+V keyboard shortcuts to paste contents. While we can understand the benefit of the selection buffer, we currently do not have plans to make updates in this area based on community feedback and current priorities.