Brief summary of issue

similar to #713
Anonymous closure is wanted here. Named closure would hold the value on first call.

Error output

Variable "$self" will not stay shared at /usr/share/shutter/resources/modules/Shutter/Screenshot/SelectorAdvanced.pm line 860.
        require Shutter/Screenshot/SelectorAdvanced.pm called at /usr/bin/shutter line 234

Extra information, such as Shutter version, display server in use (Xorg or Wayland), operating system and ideas for how to solve:

replace the code with an anonymous closure