Don't know if this is the fix, but I had the same issue...unable to save gifs. I went into settings photos..and turned off the optimize photos setting, and switched to storage of originals on my device. I have plenty of local storage so I choose to keep originals on my phone. I was able to save gifs to photos again and attach them to forum posts etc as gifs...not the still shot.
ExperiencedNoob
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