Support keeping modifier keys down until released

I remap CMD-Tab to CMD-Fn-Tab in order to use Alt-Tab in Windows over Citrix. Although this sort of works, the CMD modifier is released immediately when tab is pressed when I'd really like it to be kept down until I actually release the key.

Please could you add an option for key shortcuts to keep destination modifier keys down until the source modifier keys are released? This seems like it would be the simplest way to solve the problem. Perhaps a future enhancement could be selecting which modifiers are kept held down and which are released but that adds more UI complexity. The first suggestion could just be a simple checkbox on the key shortcut.

There are separate predefined actions "CMD Down / CMD Up" etc." which can be used instead of standard shortcuts. However I don't know whether that would work in Citrix.

@Andreas_Hegenberg there's no way to trigger the CMD-Up though. Eg if I press CMT-Tab then I can trigger:


this will trigger the app switcher. But then I want CMD-Up to occur when I release the CMD key. I can't see any way of doing that currently with BTT.

Ah I see.
There is an option to trigger a the assigned actions "on-key-up", but this only affects normal keys not modifiers.
I'll check if this can be changed, unfortunately modifiers behave a bit different than the normal keys.

Would it not be possible to implement my first suggestion, i.e. have a checkbox on the shortcut that says "keep the modifier down until released"? I think that would be useful elsewhere and solve the problem if it's possible to implement. Karabiner does this by default but it uses a kernel extension and crashes my computer frequently.

Yes, that could probably be done somehow, but I need to see what is the most feasible solution to this. Unfortunately I can not use similar code as Karabiner because that one works at a much lower level and can integrate deeper into the whole event system. (In general Karabiner is much better for real key remapping due to this)

Yeah I've just realised this myself as my shortcuts for CMD-C / CMD-V do not work reliably at all with BTT. I've sent an email requesting a refund as I bought the license a bit too hastily. Strange that last night it seemed to work so much better than Karabiner but now that I'm actually working it's become really unreliable. I guess I'll have to go back to Karabiner and hope the author fixes the crashes soon.

@Andreas_Hegenberg sorry to nag but I didn't receive any response to my email. Do you just have a lot to get through or is it possible it went into a spam folder?

I think I already triggered a refund yesterday, could you check if it was received?

I didn't receive any emails about it and it looks like the transaction is still "pending" on my credit card, which means it wasn't posted to the statement yet. Typically if it's cancelled before that happens then it will just disappear at some point but it may take a few days.