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🚀 How to increase Mastodon character limit WITHOUT forking!

Tired of the "merge hell" when updating your custom Mastodon build? You can change the 500-char limit to 7500 (or more) while staying on the official Docker images.

This works perfectly for Mastodon v4.3.0+ and @Coolify users! 🛠️

The Secret Sauce:
Instead of rebuilding the image, we use Docker Volume Mounts to overlay two specific files and set Environment Variables.

1️⃣ Backend: Create a local copy of status_length_validator.rb with MAX_CHARS = 7500.
2️⃣ Frontend: Create a local copy of compose_form_container.js and set the fallback limit to 7500.
3️⃣ Config: In your docker-compose.yml, mount these files and add:
MAX_TOOT_CHARS=7500
MAX_STATUS_CHARS=7500

Why this rocks:
✅ Update-proof: Official updates won't overwrite your limits.
✅ Zero Build Time: No waiting for hours to compile assets.
✅ Mobile Ready: Tusky/Ivory will auto-detect the new limit via API.

Full guide for sysadmins below! 👇