See attached document, the right side element. The animated GIF is not playing in Google Chrome. Works fine in Safari and firefox, on macOS.
Any hints how to make this work in Google Chrome?aGIF_vector_shape_no_play_chrome.hype.zip (550.5 KB)
Hmm that's weird! This looks like a known bug:
https://bugs.chromium.org/p/chromium/issues/detail?id=1123663
(which was partially fixed, but not for the pattern element).
And it used to be a bug in Firefox:
It doesn't look like it is resolved in Chrome Canary. One workaround is to mask the image with an inverse of the shape you currently have, and not use the GIF as the background image.
Ah… yes, thanks Daniel 
That should work in this case.
Some Photoshop, I think… and then there will be a new animated GIF with the wanted shape. (And no vector shape masking with Hype.)