GL.iNet GL-MT3000/Beryl ALX no internet after enabling Tailscale custom exit node

I recently ran into a frustrating issue with my GL.iNet GL-MT3000 (Beryl AX) when trying to use a Tailscale custom exit node. The moment I enabled it, my internet connection completely dropped—no browsing, no ping, nothing.

After some digging, I found out the culprit: the router's firewall was blocking connections when using an exit node. Thankfully, I came across a solution in the GL.iNet forum that fixed everything.

Credit to Cfm765 for sharing this fix:

On the MT3000 Admin Panel
Under menu item System->Advanced
Go into the LUCI admin panel then select Network → Firewall.
By default, below you will see 3 zones:
lan > wan
wan > REJECT
guest > wan
Click on “EDIT” on the second one ( wan > REJECT)
Then click on the second top tab “Advanced Settings” and in the covered devices dropdown select tailscale0. Save, Save and apply.

Once I made that firewall change, everything worked perfectly. If you’re dealing with the same issue, give this fix a shot!