why does lightroom classic randomly 'modify' photos, which causes an update to Flickr?

[AFC_Beachcomber]

I Use Flickr for sharing and posting my photos, directly from lightroom. When I go to publish photos, I occasionally get photos which have been 'updated/modified' but I haven't toched them. Why is this?

[Ian Lyons]

If you're seeing this issue in LrC 15 or 15.0.1, then you may be experiencing the outworking of a metadata related bug that's currently under investigation by the engineering team.

[Bob Somrak]

Unfortunately this issue has been happening in LrC for a LONG time, not just LrC 15, and Adobe has failed to resolve it.

[Ian Lyons]

True, but a new bug was introduced in LrC 15.x The image images did not show metadata errors when using LrC 14.X

[johnrellis]

"Unfortunately this issue has been happening in LrC for a LONG time, not just LrC 15, and Adobe has failed to resolve it."

Here's the bug report:

https://community.adobe.com/t5/lightroom-classic-bugs/p-photos-are-marked-for-republish-even-though-...

(Problems were occuring long before that report was filed in 2020.) Adobe reported the bug fixed in LR 13.5, but there were immediately reports of continuing problems.  I've had recurring spurious Modified in LR 14 and 15 with Flickr (Adobe's plugin) and Zenfolio (Friedl's plugin).

That bug report hasn't been reopened.