Trouble using OpenVPN while tethering with your phone? Adjust your MTU for a fix! Here is the scoop.
While tethering with a smartphone and using OpenVPN, your laptop may have trouble with things such as submitting forms (POST), uploads, or other issues. The fix is to adjust the MTU on your laptop!
After connecting to OpenVPN, run the following to adjust the MTU on tun0:
sudo ip link set dev tun0 mtu 1350
If this does not work for any reason, consider trying a lower MTU such as 1300.