In Cursor chats that get very long especially with a lot of images throughout the chat cursor slowly becomes more and more unresponsive. What’s even more odd is it’s just that chat thread, other threads aren’t that bad in that cursor window and other cursor windows are also unaffected. It can even eventually crash.
Steps to Reproduce
Make a long chat with many screenshots. This can also possibly be contributed to by pasting long text in like 200-400k messages (note this is hidden via the UI and summarized thus shouldn’t affect performance either. (This was happening with or without long messages like that to be clear, the images seem to be the main driver.
Hey, thanks for the report. This is a known issue. Long chat threads, especially with lots of images, can get progressively laggier because of how the rendering engine handles accumulated content. The fact that it only shows up in one specific thread suggests it is a memory or rendering issue in that chat panel.
A couple workarounds for now:
Start a new chat thread when the current one gets heavy. You can pull key context from the old thread via @Files, or summarize it in a .cursorrules file.
If you can, avoid pasting large images directly into the message.
If the thread is already lagging, fully quitting and reopening Cursor can help as a temporary fix. A full quit, not just a reload.
The team is aware. Let me know if you run into anything else.
Thanks will do, just wanted to make sure they were aware and hope they have a solution, namely since the image isn’t even rendered on the screen if they could at minimum stop rendering it and keep it in memory.
They could also make a tiny downscaled thumbnail of the image for preview if need, be many solutions I’m sure they are aware of.
Either way thanks for letting me know they are aware and if I run into more issues I’ll make sure to let you all know.