One too many lines highlighted when whole lines are selected

[phoenixeliot]

This is for the feature "Open on Github: File" with lines selected/highlighted.

Say you have 20 lines of text.
You put the cursor at the start of line 10, then hold shift and press down 5 times, so visually lines 10–14 are selected, but the cursor is technically on line 15 (even though it's not visible).
You then trigger "Open on Github: File".

Currently, the github URL has the line numbers #L10-L15, which includes line 15 in the highlight, even though it wasn't visually selected in the editor.

Better would probably be to not include the last line if nothing on that line is actually selected.

This occurs for me especially often because I use vim-mode, which allows selecting by whole lines, which acts identically to the repro steps I gave in terms of where the selector bounds are.