I saw the problem on your new page. I ran a couple of troubleshooting steps, which didn't obviously help, and then I noticed some of the handful of terms you had translated weren't showing in the selector at all. That's because in the View custom search you had the setting to only show options that would return results (I normally recommend this is disabled, because it can begin to have performance effects once your site starts to grow).
I disabled it, and then I retranslated the page, and the available translated terms are now showing. That may just be because the View has caching enabled, and saving the View after changing the setting would have cleared the cache.
So, as you can tell, I'm not what specifically was causing the problem, but it is working now, and I expect that as you translate the remaining terms their translations should appear in the filter dropdown.
Everything is finally working properly, the taxonomy translation problem has been solved by deactivating this option as you wrote, I think it would be interesting to deactivate this option by default in the next version.
The second problem is undoubtedly the cloning of a page with blocks, which causes a lot of problems.
As far as I'm concerned, everything's in order. Thanks for your help and all the time you've spent 🙂 you can close this ticket.
