Excellent. Have tested all various combinations in front end where issue was manifesting itself - all now AOK. Also for completeness tested in backend which had and still has no problem
Will advise others in jDownloads test team

Looks a good fix to me. Thank you.

Tested AOK on 3.3.6 as expected

Anyone got a sample data set to test with? I've installed JDownloads and made 6 categories, and six downloads for example. In a front end view with list limit set to 5, I see the pagination and it works (before applying the patch).

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I think JDownloads fixed it in their latest release. You would have to use an older one.

Sorry about delayed response but have been away. Yes jDownloads code was changed to avoid problem. I do have a previous jDownloads zip if you would like it. Approx 24Mb.

Can you link that here? I'm sure that would help.

Updated the PR so it also clears the offset. That doesn't change anything for all databases except PostgreSQL since the others already clear the offset together with the limit.

@ColinM2 If you can link that file, then it sure would help getting this tested.

@test I added this patch to the current staging branch and installed the test data to a mysql and postgresql installation. As there is no easy test case I manipulated the _getListCount function.

First I commented out the "fast part" - the first if block - and tested the "article category list" with the "inefficent part" - what comes after this block. That did work.

Then I added $query->group('a.id'); before the "inefficent part" and tested with the mysql installation. That did work too.

Are there other ideas how to test this?

Are there other ideas how to test this?

I think that's about the best you can do it.