Avatar net::ERR_HTTP2_PROTOCOL_ERROR 200

Hello,
I encounter a weird error since some weeks ago. After an update (NC19 to 20) but I got the same error after the next update (NC20 to 21). All user avatar are not showing. I got this error in chrome console:

GET https://[NEXTCLOUD URL]/index.php/avatar/[USER_NAME]/32?v=2 net::ERR_HTTP2_PROTOCOL_ERROR 200.

Moreover, I get an another error (but I don’t know if it is linked):

Error while trying to use the following icon from the Manifest: https://[NEXTCLOUD URL]/index.php/apps/theming/icon?v=9 (Download error or resource isn't a valid image)

Do you have any idea ?

Nextcloud version: 21.3.0
Operating system and version: CentOS 7
PHP version: 8.0.8