@elextr
I suggest all the signal scripts be checked for existence at plugin start, not checking the file system every signal.
What problem does this really solve? Only 0.001 nanoseconds is spent per keystroke checking that the file exists. That results in 4.38 min for a year of non-stop typing at 100 wpm. Even pro-writers would be hard pressed to lose more than 30sec per year of normal use to the checks. Meanwhile, performing the check once at startup eats up programming time, introduces the potential for bugs, and wastes users' time when their scripts don't work and they have to spend time researching the command to update the plugin state.