Implement 'pipe'

[karolyi]

Prerequisites

• Tried the most recent nightly build
• Checked if your issue is already reported.

Is your feature request related to a problem?

Yes, pipe is not supported and so the editor UI doesn't load. For it to work in dovecot, you'll need the vnd.dovecot.pipe plugin required.

Describe the solution you'd like

pipe is a valid command in sieve for redirecting the email into a script. I have it in my own manually edited sieve file, which when trying to load with the plugin, gives an error.

Additional context

Just an additional info, the UI should be adjusted for handling preset colors. I have my thunderbird colors overridden from the settings, which makes it look like this:

As it can be seen, the checkboxes (toggles) are unable to see which state they're in. Also, the editor looks like this (also notice the require line for the pipe plugin):

I can live with that, but for example, selected text is not displayed as selected.
Excerpt of the visual editor:

[thsmi]

Concerning the pipe extension:

The prefix (vnd) indicates, it is a vendor specific, non even standardized in an rfc. It is dovecot specific. Implementing support for the extension is not difficult but needs some time and is definitely a low priority task. So don't expect this to land soon. If you want to speed it up feel free to contribute a patch.

Concerning the Dark mode:

The UI uses Bootstrap (https://getbootstrap.com/) from Twitter as Framework. Which does not provide an official dark theme and thus has no support for a dark mode.

Bootstrap uses complex styling rules and fine tuned styles, so it would be a miracle if just changing the HTML Default colors would do the job. So there is not much which could be done here.