Storage Format Editor shows loss of css classes after a page upgrade

[David May]

We use custom css classes on our pages for our PDF export. In August 2024 we moved from Confluence server to Confluence cloud and chose to use Storage Format Editor for Confluence FREE by K15t Labs. This solution works great.

However, with the forced updated of our legacy pages, the custom css is lost. We have no workaround.

1. Update page and save update (css is lost)
2. Go to Updated Page > ⋯ > Version History and open the page before the update
3. Go to Versioned Page > ⋯ > View Storage Format and copy content (has css)
4. Go to Updated Page > ⋯ > Apps > Edit Storage Format
   1. paste from #3
   2. Save
5. The Updated page now has the css again
6. Modify the page with any new next and save
7. (!) The save page no longer has the css

It looks like the new editor not only strips existing css from legacy pages on conversion but also restrips any newly added css on every save.

This is a nightmare. Does anyone have any solutions? I'm also reaching out to K15t labs.

[Darryl Lee]

Hey @David May - Did you hear anything from K15t Labs? I had an odd issue with their tool not properly handling edits I made to images that had links, but then I couldn't reproduce it and I moved on to the next fire. :-/

[thomas]

Hey everyone,

I'm one of the developers that work on the Storage Format Editor at K15t so I can give some details on the issue. 

This issue is likely due to Atlassian shifting away from Storage Format and towards ADF for their editor and page rendering. In ADF custom CSS is not directly supported, only a few very limited styling options can be stored (pretty much the ones that the new Confluence editor already provides).

 Confluence seems to still store a storage format representation of the page when using an storage format editor such as ours but since the new Confluence editor seems to exclusively work with ADF it will lose any information that can't be represented in ADF on the next page edit.

There's unfortunately nothing we can do about this on our end as the Confluence editor is the problem here. You could reach out to Atlassian support about this but I don't know if they will do anything about this since this implementation was likely an intentional choice on their side to reduce the amount of complexity in the Confluence page storage medium.

Cheers,
Thomas