Wizard101 severe fps drops during network operations

[nomesc]

Compatibility Report

• Name of the game with compatibility issues: Wizard101
• Steam AppID of the game: 799960

System Information

• GPU: RX 7900 XT
• Video driver version: Mesa 26.0.3
• Kernel version: 6.19.9
• Link to full system information report as Gist:
• Proton version: experimental-10.0-20260312

I confirm:

• [*] that I haven't found an existing compatibility report for this game.
• [*] that I have checked whether there are updates for my system available.

steam-799960.tar.gz

Symptoms

Game runs at 144 fps locked normally.
The fps drops to 17 fps when at least one of the following is true:

• You receive a message from a player and have the chat window opened
• You collect reagents and have the chat window opened (equivalent of receiving a message from the server)
• You send a message
• You have the character window opened (press C on the keyboard)
• Another player enters the same area as you
• You enter an area with other players

Reproduction

This reproduces 100% of the time if you do one of the following:

• You receive a message from a player and have the chat window opened
• You collect reagents and have the chat window opened
• You send a message
• You have the character window opened (press C on the keyboard)
• Another player enters the same area as you
• You enter an area with other players

[kisak-valve]

Hello @nomesc, we're using one issue report per unofficially supported game title, so I've gone ahead and transferred this issue report to #1875 (comment).