Encoding error when enabling W3 Total Cache

Hello, so I have a encoding error on all my website when I enable W3TotalCache
This happens on private browser exclusively

Problem goes away when I disable the plugin or use regular navigation

For information, I had encoding errors on my website 1-2 weeks ago until I resolve it.
So the issue might be that W3 total cache keeps a former version on my side.

But when I do purge caches, it doesn’t work
I just would like to be sure W3totalcache works correctly and does not create this encoding error by itself.

Could someone let me know?
Thanks!

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