Any successful email composer implementations with CKEditor 5?

Question

The Problem

We are trying to get the best configuration for CKEditor 5 to allows users to compose responsive emails, reply to emails and copy-paste content into it. Our software can also capture emails and display them.

But we are having weird rendering issues, they include:

• Tables gets wrapped in tags
• Image Alignment and Table Alignment works in Gmail but not in Desktop Outlook
• Outlook ignores table cell background color, inside text color, and table size
• Gmail renders background color and inside text correctly but ignores table size

We have tried for a few months already and there are always issues. The last things we tried are:

• https://www.npmjs.com/package/ckml -> works slightly better but no fix for tables
• https://www.npmjs.com/package/ckeditor5-build-classic-email -> just strips out the modern email support like tables.

Both builds are missing the html-support plugin or reference an unknown package ckeditor5-preserve-style

What I'm looking for

I understand that every email client will have it's own rendering rules and acceptable tags/properties.

• Is there a CKEditor 5 configuration that is designed for maximum support for email editing and rendering?
• Is there a pre-built engine (JS, C#, ...) that can take a less compatible CKEditor HTML and make it more compatible by adding missing things into head, replace , do magic for tables, ...? And also still support converting it back to the original for future CKEditor-friendly editing.
• Has anyone had a good implementation of CKEditor 5 for email that they can share?