Upgrade PDF Designer v.8 to v.9/php8

We need to redesign a site and convert all pages to v.9 due to PHP8 update of hosting company. The site has over two hundred pages containing technical illustrations and relies heavily on Bitter dev’s PDF Designer. Unfortunately the addon has disapeared from marketplace and developer is unavailable since weeks if not months.

How do we deal with such a problem when developer offers no upgrade or support anymore?
Is there a similar addon which we have to rebuild the site? We have tried the Ckeditor PDF export function without success.
Should we try to make the addon compatible to php8/cms v.9?

Thank you for suggestions to this topic.

How old is that addon, from 5.6 era or later?
5.6 requires full rework, but if its 5.7 or better 5.8 transition is more straightforward.

If you are content with it (and can’t find better replacement), it would be the best just to update it.
Most stuff is just fixing pretty basic undefined variable/array key errors, but there can be some not backward-compatible functionality that requires some more “knowledge”. It also depends how complex addon actually is.

Thanks for replying. Addon was purchased in 2019 for cms v.8.5.
You are right, I think its doable and we try fixing it.
We’d leave License intact, I guess thats OK.