Hello,
I've attached complete test file. The test body is:

  zpty_start
  zpty_input 'stty 38400 columns 80 rows 24 tabs -icanon -iexten' nl
  zpty_input 'rh_widget() { BUFFER="ls"; region_highlight+=( 0 4
"fg=#12569a" ); echo yes; }' nl
  zpty_input 'zle -N rh_widget' nl
  zpty_input 'bindkey "\C-a" rh_widget' nl
  zpty_input 'zle -la | grep rh_widget' nl
  zpty_input 'bindkey | grep rh_widget' nl
  zpty_input $'\C-a'
  zpty_stop
0:region_highlight
*>*ls*

The result is always:

Pattern match filead, line mismatch (1/3):
 <*ls*
 >rh_widget
 >"^A" rh_widget
 >zsh: command not found: ^A

Note that the 2 middle lines confirm the widget is created and bound to Ctrl-A.

I can change Ctrl-A sequence to just letter "a", and the result is the
same. I've tried also without the first stty command (I was looking
for some needed initialization in Y0* completion tests, that's why
it's there). What can be the cause?

Ctrl-T was invoking TTY "status" command, which on BSD gives system
load. So I've changed to TTY-unused Ctrl-A. I just need to invoke zle
widget so if there is other method (zle -F didn't work) I can use it.

-- 
Sebastian Gniazdowski
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