Web GL failing with the following error, any ideas?

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same here! In my case the error disappeared, when i removed all the blank lines in the .htaccess file of my webgl client folder. Not sure if that was really the problem, but it might be worth a shot.

I ran into this as well. I’m not sure if it’s an htaccess thing for me… it seems to fail only occasionally…

Running version 5.4.0f3

Getting the same issue building with 5.5.0f3, just like @bererton it only fails occasionally. I tried toggling Development mode, Strip Engine code, still see this error.

I then tried building to a new directory (literally just a copy of the previous build directory with the version number increased by 1) and it worked, but I’m unsure if this is coincidental or not. Also note it only worked in Firefox, still get an error in IE with that same build.

I’ll be building somewhat frequently so I’ll see if the new directory name is a reproducible workaround. Didn’t touch the .htaccess file yet.

The cause is listed in this conversation: https://forum.unity.com/threads/uncaught-assertion-failed-s_globalmetadataheader-metadatacache-cpp.439913/.