Delay is inconsistent when using btt://trigger_action

Describe the bug

When I attempt to trigger a BTT action through "btt://trigger_action", if it contains a "delay next action," the delay doesn't always work.

For example, if I run the following terminal command 10 times (I did this just now on my machine)...

open -g 'btt://trigger_action/?json={"BTTShortcutToSend":"0","BTTAdditionalActions":[{"BTTPredefinedActionType":129,"BTTPredefinedActionName":"Delay Next Action","BTTDelayNextActionBy":"0.5"},{"BTTShortcutToSend":"11"}]}'

On 4 of them, it behaves as expected (outputs “a”, then pauses, then outputs “b”).
But on 6 of them, it outputs “ab” immediately (with no pause in between).

So, the "delay next action" appears to not trigger sometimes (but the other actions always work).

I cannot figure out why or when it decides to trigger--it appears random to me.

Any help is greatly appreciated.

Device information:

  • Type of Mac: MacBook Pro 2015
  • macOS version: 10.14.6
  • BetterTouchTool version: 3.335