It would be awesome if someone actually built an infinite canvas application that didn't run on the browser, so that you could actually use it effectively.
Currently, the majority of infinite canvas applications begin to noticeably lag and stutter after a while, and start to have syncing inconsistencies especially in their "multiplayer" mode.
If you are on Mac then there is one called Muse (https://museapp.com/) by the authors of the site in this thread and it's as smooth as you would expect.
They lag because some Porter and Duff layer composition modes require textures at the size of the parent bounding box enclosing all objects. Bigger the texture, the more resource demanding the composition becomes.
A little tangential to this but my favorite drawing program for sketching, Mischief, did this perfectly for art. Sadly the company shutdown and there are no more updates.
“Knockoff” is not giving Figma its due credit. People loved Sketch, and now everyone in product design is using Figma. You think that happened by Figma being a knockoff?
Currently, the majority of infinite canvas applications begin to noticeably lag and stutter after a while, and start to have syncing inconsistencies especially in their "multiplayer" mode.