There is no way to bind the 2 extra thumb buttons on my mouse to things such as sprint. Also there is no way for one of the buttons to select my sword on the hotbar like a macro. This is a bug.
MC-28551
Cannot bind extra mouse buttons
Resolved
Invalid
0
This site is for bug reports only. Feature and improvement suggestions are not currently being tracked here. There is no sprint button nor can 1-9 be changed.