I'm running Smush Pro 2.7.6 in a multi-site environment. When Smush is deactivated and I upload the attached gif file it works fine. If Smush is enabled and I upload the attached gif file it doesn't work. I've verified this by going directly to the URL of the gif file after upload, so it's not an issue where I'm calling some WP function and it's sending me back the wrong thumbnail.
As a workaround while you look into avoiding smushing animated gifs, is there a way to get Smush to skip all gif files that doesn't involve editing your code? I'm trying to use the wp_smush_image filter but I'm not having any luck. Also, I'd rather not have to use that one because it requires an extra lookup to each post record (since it only passes in the attachment ID).
I appreciate your advice.