Discord, Slack, and Teams on Mac: Cache vs History vs Downloads

Discord, Slack, and Teams all get large on a Mac for the same reason, and the fix is the same decision each time: separate cache from history from downloads before deleting anything. Cache is regenerable and safe to clear; message history and saved files are not cache, and clearing them by mistake is the failure this guide is written to prevent.

This is a decision guide, not a "clear all caches" tip list. It uses "Mole" only for Mole for Mac at mole.fit and its own mo command line tool, and it does not quote per-app gigabyte figures, because they vary too much to be useful. Apple's own Messages is a different app; to clear its attachments see clear Messages storage on Mac.

The same four kinds of data in every chat app

Every desktop chat app splits its disk use the same way. Sort what you see into these four kinds first, and the per-app steps below become obvious.

The order matters: decide which kind it is first, then act. A large number is not a reason to delete; a confirmed cache is.

Discord on Mac

Discord keeps a cache of media previews and avatars that grows with use. The desktop client has no documented button for clearing it, so the manual route has to stay narrow. Quit Discord completely with ⌘Q (closing its window leaves it running), open ~/Library/Application Support/discord/ with Shift-Command-G in Finder, and move only Cache, Code Cache, and GPUCache to the Trash; Discord rebuilds them on the next launch. Leave Local Storage and the rest of the folder alone, and do not trash the whole discord folder, which also holds your local settings and sign-in state. The Discord uninstall guide covers the other files it leaves on a Mac.

History in Discord largely lives on its servers, so signing in reloads your conversations; the local footprint is mostly cache and any files you downloaded. Review the downloads location before removing anything, and quit Discord before you inspect any Library folder so you are not touching files it holds open.

Slack on Mac

Slack separates a workspace cache from local state, and large media in busy workspaces is usually the cache. Prefer Slack's own clear-cache or troubleshooting step, documented in Slack Help, rather than guessing at folder paths. Where the folders are depends on how you installed Slack: the direct download from Slack's site keeps them in ~/Library/Application Support/Slack, while the Mac App Store build is sandboxed and keeps its data inside ~/Library/Containers/com.tinyspeck.slackmacgap. The Slack uninstall guide links Slack's troubleshooting page.

Slack's Clear Cache and Restart restarts the app and reloads local cache; it does not delete messages held by your workspace. Clearing app data is a different step and can sign you out. Review files you saved or exported separately.

Microsoft Teams on Mac

Microsoft documents the cache reset for new Teams on Mac: quit Teams with ⌘Q, delete two folders, ~/Library/Group Containers/UBF8T346G9.com.microsoft.teams and ~/Library/Containers/com.microsoft.teams2, then start Teams again. Moving the two folders to the Trash in Finder does the same job and is easier to undo than the rm -rf commands in Microsoft's article. The next launch takes longer while Teams rebuilds them, and you may have to sign in again. Chats and channel messages are kept in Microsoft 365, not in these folders, so the reset does not lose them. Microsoft also notes that it does not fix missing messages or chats that will not load, and that it deletes the diagnostic logs support would need, so keep it for problems with the local client.

Touch only those two folders. Other UBF8T346G9.* folders in Group Containers belong to Office, OneDrive, and other Microsoft apps. A leftover ~/Library/Application Support/Microsoft/Teams is where the older classic Teams client kept its cache; review that subfolder on its own, and never the Microsoft folder above it, which other Microsoft apps share. Files you downloaded from chats or meetings are separate from all of this. The Teams uninstall guide covers the components its installer can add.

A side-by-side decision checklist

1. Measure first: find the app's folders in Storage settings or a disk view and see which is actually large.
2. Classify each into cache, history, or downloads using the table above.
3. Use the app's own clear-cache step before touching any Library folder.
4. Quit the app completely, then review its ~/Library/Caches and ~/Library/Application Support entries with care.
5. Never bulk-delete a shared vendor folder because one app looks large; confirm ownership first.

For the general rules behind "is this regenerable?", see which Mac caches are safe to delete, and for reviewing Library residue after an uninstall, review leftovers before you delete.

Where Mole fits

Mole 1.15 lists these apps in Clean's Communication section, and its reach is narrower than the manual steps above:

• Discord: Cache, Code Cache, and GPUCache under ~/Library/Application Support/discord, plus ~/Library/Caches/com.hnc.Discord.
• Slack: the direct-download folders Cache, Code Cache, and GPUCache under ~/Library/Application Support/Slack, plus ~/Library/Caches/com.tinyspeck.slackmacgap. For the App Store build it only sees the generic cache entries in the container's Data/Library/Caches.
• Teams: ~/Library/Caches/com.microsoft.teams2 and the cache entries in ~/Library/Containers/com.microsoft.teams2/Data/Library/Caches. It does not run Microsoft's reset: it never offers either whole folder, and uninstalling Teams with Mole leaves the shared UBF8T346G9.com.microsoft.teams group folder in place.

These rows are rebuildable cache, so they are selected by default. Rows under Application Support and Containers appear only with Full Disk Access, and while Discord, Slack, or Teams is running Mole holds back its rows, so quit the app before scanning. History, downloads, and sign-in data are not on the list. Scanning is free without a license, and you decide what to remove. For exactly what it removes and what it refuses to touch, see is Mole safe.

Further reading

• Which Mac caches are safe to delete: the regenerable-versus-not rule for any app.
• Clear Messages storage on Mac: the same job for Apple's Messages, a different app.
• Review leftovers before you delete: how to judge Library residue by ownership.

FAQ

Will clearing cache log me out or lose history?

Clearing cache may make an app reload or ask you to sign in again, but it does not erase messages held by the service. Slack's Clear Cache and Restart is distinct from clearing app data, which signs you out. Files you downloaded are separate; review those before deleting.

Can I delete the whole Slack or Discord folder?

Deleting a whole app folder is an uninstall-level action, not a cache cleanup. It removes local state and any local-only files together, so treat it as removal, not reclaiming. Clear the cache through the app first, and only remove the folder if you actually mean to uninstall. Teams is the one documented exception: Microsoft's cache reset for new Teams removes its two folders, as described above, and your chats stay in Microsoft 365.

Do Electron apps share the same pattern?

Largely yes. Many desktop chat apps are Electron-based and keep a rebuildable media cache plus local state under Application Support, so the cache-versus-history decision transfers. The exact folder names still differ per app and per build, so confirm before deleting.