Fossilize is spamming warnings to my log

[konomikitten]

When I start Warframe on Steam I see the following lines in my journal log:

Mar 16 16:07:31 debian steam[6391]: Fossilize WARN: Graphics pipeline handle 0x00007f23609a8230 is not registered.                                    
Mar 16 16:07:31 debian steam[6391]: It has either not been recorded, or it failed to be recorded earlier (which is expected if application uses an ext
ension that is not recognized by Fossilize).

This generates an extremely large amount of messages:

$ sudo journalctl --boot=0 --output=cat --grep='Fossilize WARN: Graphics pipeline handle .* is not registered' | wc -l
20085

So much in fact that journal reports that it has suppressed messages:

Mar 16 16:03:16 debian steam[6391]: Fossilize WARN: Graphics pipeline handle 0x00007f23586f0fb0 is not registered.
Mar 16 16:03:16 debian steam[6391]: It has either not been recorded, or it failed to be recorded earlier (which is expected if application uses an extension that is not recognized by Fossilize).
Mar 16 16:03:39 debian systemd-journald[493]: [🡕] Suppressed 11378 messages from user@1000.service
Mar 16 16:03:39 debian steam[6391]: Fossilize WARN: Graphics pipeline handle 0x00007f2368dc6d30 is not registered.
Mar 16 16:03:39 debian steam[6391]: It has either not been recorded, or it failed to be recorded earlier (which is expected if application uses an extension that is not recognized by Fossilize).

Could something be done about this?

I tried using setting the launch options to FOSSILIZE=0 %command% but this didn't stop the messages.

[konomikitten]

I was able to stop the spam in Steam by disabling Shader Pre-Caching in Downloads.