Also note my suggestion, coincidentally, isn’t the same as Home and End keys. They are to move selection! 
Maybe those would be different enough to justify listing.
And J and K comes from vi, I suppose. H and L there act as Pg Up and Pg Down, but Home and End would be close enough! 
Finally, in the help, J and K’s translation are reversed as Down and Up - it’s saying “Move selection ↑ ↓” while it should say “Move selection ↓ ↑”.
Me and a lot of my colleagues use the Built-in OSX Command shortcut keys. These are sane defaults based off of the same Bash shortcuts used throughout Linux.
Control + h to backspace
Control + b to move the cursor backward (same as the left arrow)
Control + k to clear a line of text
We use the shortcuts literally everywhere throughout OSX, from the command line to Gmail, and they are second nature to the extent that I can’t mentally turn them off.
I can understand the desire for markdown keyboard shortcuts, but these collide with widely used Control shortcut keys, and make typing in Discourse a frustrating experience.
Please make an option to toggle these markdown shortcuts off.
Word. Although I wouldn’t like to turn all of them off, and I’d instead just replace a few (such as CMD + L for CMD + K or leave just CTRL + L). 
I suggest we change most of the Markdown shortcuts to use Ctrl + Shift as modifier keys. I just looked at outlook.com which does the same thing in their format toolbar.
E.g. the shortcut for the emoji selector is Ctrl + Shift + Y
I’d really like to have the j and k shortcuts for navigating the full page search results (similar to Google search and the topic list in Discourse).
PR welcome, this should be a very simple change.