Is Thursday 8pm to midnight GMT a particularly busy time for the servers?

[aeristoka]

Do the Module Check and World Size Check.

That all smacks of Module problems first off.

World Size Check

Introduction An oversized world is a world that uses a lot of data storage. A world that is oversized, or takes up too much data storage can result in difficulties/slowness loading into the game, or outright instability while playing. We explain why world size matters, how to check world size, and resolve any issues with it below. Why world size matters World size matters because users may start to see increased loading times around the 30+ MB mark. This is because Foundry VTT sends the worl…

Trouble with Modules

Introduction More often than not, if Foundry VTT (on The Forge, or elsewhere) is running slowly, it is usually the fault of module issues (whether a module issue by itself, a module conflicting with another, etc.). This article is intended to give you the tools to find issues with the modules you use so that you can go about running your games, and not worry about fighting the software. Performing a Module Audit First, confirm that there is a module issue by enabling safe configuration for t…

Something else to check (AFTER those two), is the GPU being used by various users’ browsers: WebGL Report

Specifically look at the “Unmasked Renderer”

If it’s Intel UHD, know that FoundryVTT 0.8.x is REALLY hard on those, you’ll have to turn off graphics settings, and turn down FPS to stabilize (if that’s it).