Telegram's desktop client is the most aggressive media hoarder most people install. Because "everything is cloud", it feels weightless — until you check ~/Library/Group Containers and find 10-50 GB of videos, voice notes and sticker packs already on disk.

1. See the damage

du -sh ~/Library/Group\ Containers/*.ru.keepcoder.Telegram 2>/dev/null
du -sh ~/Library/Group\ Containers/6N38VWS5BX.ru.keepcoder.Telegram/* 2>/dev/null | sort -h | tail -5

(The store path contains account archives: account-X/postbox/media.)

2. The setting that prevents it

Telegram → Settings → Data and Storage → Storage Usage: set "Keep media" from Forever to 1 week / 1 month, then tap Clear All under the cache size readout. This is the single highest-value toggle in the app — most installations ship on Forever.

3. Manual purge for existing bloat

The in-app Clear All is the supported path and keeps your cloud data intact — nothing in Telegram's cloud is deleted, only local copies. Deleting files under Group Containers by hand also works when the app is fully quit, but the in-app route avoids edge cases with the postbox database.

4. Per-chat reality check

Settings → Data and Storage → Storage Usage also ranks chats by cached size. Big channels with video-heavy history are the usual culprits; clear them individually if you want to keep frequently-used groups snappy while nuking the hoard.

Same disease, other apps

WhatsApp, Slack and Discord all share the keep-everything default — the Slack/Discord paths are in our chat-app cache guide. For the full Mac cleanup map, start at System Data explained or size your situation in ten seconds with the waste estimator. If you would rather never open these settings again, MacCleaner PRO-class tools sweep messenger caches on a schedule.