How can I debug lost keyboard input?

[Andy Spiegl <zsh.Andy@xxxxxxxxx>]

Hi,
my problem I tried to summarize in the subject line is:

Since the recent OS upgrade to Ubuntu 18.04 my zsh (5.4.2) behaves
strangely when typing keys together with Meta + Shift.  The first time I
type e.g. Meta+Shift+f nothing happens.  The second time (and all following
times) the bound function is executed and everything seems normal.

I've bound finer-forward-word to Meta+Shift+f and finer-backward-word to Meta+Shift+b
They are defined as follows:
--------
finer-forward-word() {
  local WORDCHARS=$WORDCHARS_FINER
  zle forward-word
}

finer-backward-word() {
  local WORDCHARS=$WORDCHARS_FINER
  zle backward-word
}
--------
export WORDCHARS='*?_-.[]~=/&;!%^(){}<>+:@'
export WORDCHARS_FINER='?~&!%'
zle -N finer-forward-word
zle -N finer-backward-word
bindkey "F"		finer-forward-word
bindkey "B"		finer-backward-word
--------

All my other keybindings work normally.  Just these two are crazy.
BTW if I bind the functions to a different key the same thing happens.
Uhm, as if the function would have to be loaded/initialized on the first try?

I know I should let you know about the rest of my zsh config but it has
grown pretty large over the last decades. :-)  But nothing except some
aliases has changed during the last months so the problem must have to do
with the upgrade.

Any ideas how I can debug this?

Thanks,
 Andy


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