When attaching cursor to a running container for the first time (using Anysphere Dev Containers), it used to directly check the “.vscode/extensions.json” and ask you, if you would like to batch install the extensions via a pop-up.
A few releases ago this is not the case anymore, so after you attach cursor to the running container, you always have to go to the “Extensions” Tab and manually type in @recommended to show all recommended extensions and then install them manually one by one.
Second Bug
When using Microsoft’s Dev Containers extension, you have to only install the extensions only once, when you attach vscode to a container for the first time. Even if you restart the PC (or WSL) and then reattach to the same container, Microsoft’s Dev Containers extension, will know, which extensions you installed the last time you attached to this container and will reinstall them automatically.
When using the Anysphere Dev Containers extension, you always have to manually install the extensions after reboot. Which gets quite annoying.
Also you always have to manually reindex the project code, if it exceeds a certain size in the cursor settings, even if you already reindexed it once, it doesn’t keep on reindexing automatically.
Steps to Reproduce
First Bug
Have a container running with a VSCode extensions.json in /var/www/html/.vscode/extensions.json
Attach Cursor to /var/www/html using the Anysphere Dev Containers extension
See no install pop-up
Second Bug
Have a container running with a VSCode extensions.json in /var/www/html/.vscode/extensions.json
Attach Cursor on /var/www/html using the Anysphere Dev Containers extension
Install all extensions manually
Restart WSL / computer
Reattach to the same container on /var/www/html
The extensions are not automatically installed and need to be installed manually again.
Expected Behavior
First Bug
The install Popup should appear
Second Bug
The extensions should be automatically installed on reattaching Cursor
A couple of quick questions so we can narrow this down:
Bug 1 no recommended extensions popup: When you attach to the container, are you using only .vscode/extensions.json for recommendations, or do you also have a .devcontainer/devcontainer.json with extensions listed in customizations.vscode.extensions? Extensions in .vscode/extensions.json are treated as recommended and used to show a prompt, but if you want auto-install, listing them in devcontainer.json under customizations.vscode.extensions is usually more reliable:
Bug 2 extensions lost after reboot: This sounds like a real gap in the Anysphere Dev Containers extension vs Microsoft’s one. I’ll flag this to the team. Can you confirm if you’re doing a pure Attach to Running Container flow, or using a devcontainer.json based flow?
Re-indexing: Is this related to the large project file limit in settings? After reboot, does the index disappear completely, or does it show as partially indexed?
Do you remember roughly which version the popup was still working in? That would help us track down when the regression started.
Unfortunately, the .devcontainer.json isn’t properly used when attaching to a running container, where the container itself contains the .devcontainer.json. There is this old issue, where this is talked about:
This is an age old task for us, where we tried several methods to auto install extensions, but never really succeeded. All documented here:
But it won’t auto install any extensions, because of the reasons listed above in the issues. As a workaround we added the .vscode/extensions.json, so when we attach via command, we get the little prompt to install the recommended extensions. And in the case of VSCode the install prompt appeared and the extensions kept being installed even after reattaching after reboot. But for Cursor the install prompt doesn’t show up nor are the extensions still installed after reboot.
Regarding the re-indexing after reboot: It shows, that the index is gone completely, but once pressing “compute index” it seems to find an existing index and only updates it:
Hey, thanks for the detailed follow-up and the GitHub issue links. That context is really helpful.
Here’s what I’m tracking:
Recommended extensions popup regression .vscode/extensions.json used to trigger the install prompt when attaching to a running container, but it doesn’t anymore. Got it that devcontainer.json won’t work for Attach to Running Container flows.
Extensions not persisted after WSL or PC reboot
Microsoft Dev Containers keeps installed extensions across reboots, but Cursor doesn’t. That’s a real gap.
Index lost after reboot
From your screenshot, it finds the existing index and updates it, but not auto-resuming indexing on reattach is definitely inconvenient.
I’ve flagged all three issues with the team. No ETA yet, but your report, especially the GitHub issue links showing the attach-to-running-container limitations, helps us prioritize.
One question: do you remember roughly which Cursor version still had the recommended extensions popup working? That would help narrow down when the regression started.
No problem if you don’t remember the exact version. Having a rough 2-month window is enough to narrow down the regression search.
All three issues have been shared with the team. There’s no timeline yet, but I’ll post here if there are any updates. Let me know if you run into anything else.
