Make it behave more like notepad++

[stderr-to-devnull]

1. Selecting several lines and pressing TAB will overwrite content with TAB, instead of indenting; although this can be achieved with ALT+SHIFT+ARROWS, it is not so easy to use
2. Bring back the CTRL+K / CTRL+SHIFT+K functionality: comment/un-comment selected lines (# followed by one space), this is extremely useful to have; right now this key combination just deletes the selection
3. Allow user to alter default language syntax highlighting, based on file extension. For example, right now notepadqq applies ZSH for highlighting for .sh files and I want to make it apply BASH instead.
4. In notepad++, going with mouse just on the left of the line numbers, in the left strip, the mouse cursor would invert horizontally and on click + drag, all corresponding lines could be selected
5. Was glad to find the notepad++ solarized dark but main notepadqq has way more themes to choose from, even though I use this one