Bug? Image Flip in Clip Attributes Doesn't Work

Running 18.6.5 Studio, Mac

I've been given some footage that was shot upside down. In previous projects I'd select those clips, open Clip Attributes, and either use the image flip toggles or rotate Image Orientation 180° to set the clips up correctly. But in 18.6.5 neither of those things work. I've tried it with originals and proxies, single clips and batches. DR seems to be ignoring the settings.

Anyone else experiencing this? Is it some super secret setting I've failed to enable?

Works fine for me here on a Mac, so it can't be a bug in 18.6.5 per se.

Are you using proxies? I believe that once you activate proxies several attributes like this stop working. Which to me is clearly a bad thing. I’ve reported it before.

You're right, that might be. I rarely use proxies on this Mac.

P.S.
Just tried, if I flip the original and then generate proxies, they are flipped too.

Which means you can’t use the external proxy generator…

No. It doesn't know about changes in Clip Attributes, obviously the two programs don't seem to communicate. Or, to say it differently, DR does not check for changes in the Clip Attributes of an original to apply them to externally generated proxies.

I made the proxies in Resolve, not Proxy Generator. But yeah it does seem to be an issue with the proxies because I just did the flip/rotate to a different clip for which I haven't made a proxy and it worked as normal. So it's an issue with proxies, which at least narrows it down but is still frustrating.

For some reason I can’t explain BMD decided to bake various things into the proxies. In my opinion this is a BAD IDEA. I wrote a lot about it here:
viewtopic.php?p=927900#p928045

The current behavior of ignoring certain attributes when proxies are on is not a bug but rather a design decision to avoid the attribute being acted upon twice: once when generating the proxy and a second time when rendering the proxy.

Again I claim this is a bad design decision and it causes all manner of problems. But it’s not a bug.

This sort of thing is exactly the reason that it’s important that we be able to discuss things here with BMD. Without such discussion issues like this can’t be avoided. And when they do happen users have no way of having any confidence that they’ll be addressed.

Here are quite a few posts on the same topic:
viewtopic.php?t=144376
viewtopic.php?p=1002907#p1002907
viewtopic.php?t=186180
viewtopic.php?p=926097#p926097
viewtopic.php?f=21&t=164588#p868833
viewtopic.php?f=21&t=165164