Toolbox plugin 1.4.10 not working for RoundCube 1.4.X release

[trollkotze]

Hello!

Please excuse if this is in the wrong category. I don't know the difference between "API based Plugins" and "Old-style Plugins".

I am using RoundCube v1.4.11 and having issues with the Toolbox plugin v1.4.10.

The menus for the toolbox plugin (setting mail forwarding, alias addresses, vacation message, ...) are present in RoundCube, but when clicking on them, nothing is rendered.

The error log (in logs/errors.log) gives me this message:

[20-Mar-2021 08:17:43 Europe/Berlin] PHP Fatal error:  Uncaught Error: Class 'rcmail_action' not found in /var/www/html/webmail/plugins/toolbox/toolbox.php:1204
Stack trace:
#0 /var/www/html/webmail/program/include/rcmail_output_html.php(1359): toolbox->tool_render_form(Array)
#1 [internal function]: rcmail_output_html->xml_command(Array)
#2 /var/www/html/webmail/program/include/rcmail_output_html.php(1209): preg_replace_callback('/<roundcube:([-...', Array, '<roundcube:incl...')
#3 /var/www/html/webmail/program/include/rcmail_output_html.php(781): rcmail_output_html->parse_xml('<roundcube:incl...')
#4 /var/www/html/webmail/program/include/rcmail_output_html.php(615): rcmail_output_html->parse('tooledit', false)
#5 /var/www/html/webmail/plugins/toolbox/toolbox.php(530): rcmail_output_html->send('toolbox.tooledi...')
#6 /var/www/html/webmail/program/lib/Roundcube/rcube_plugin_api.php(522): toolbox->init_html()
#7 /var/www/html/webmail/index.php(292): rcube_plugin_api->exec_action('plugin.toolbox....')
#8 {main}
  thrown in /var/www/html/webmail/plugins/toolbox/toolbox.php on line 1204

Apparently the plugin somehow needs a class called rcmail_action from RoundCube, which is not present in the program/include directory for RoundCube v 1.4.11.
Looking at the GitHub master, the file rcmail_action.php exists there in the include directory, but it is apparently not (yet?) part of a released (non-beta) version.

The Toolbox plugin README says it should work with RoundCube 1.4.X. Given that the required rcmail_action.php is not present in RoundCube 1.4.X, that is not the case.
Where is the error?
Maybe the release tarballs from RoundCube GitHub are incomplete? Or is the plugin wrong for claiming that it should work with RC 1.4.X?
How can I get it to work? Is it safe to just copy the missing rcmail_action.php file from the GitHub master into program/include and see what happens from there?
I don't want to install a Beta version or the GitHub master. I would prefer a stable version of RoundCube and everything.

Thanks for any hints and ideas.

[alec]

Looks like you're using git-master version of the plugin, not 1.4.10.