I was told that there was an issue with the speedometer if a user teleported to another world. I attempted to fix it in this update

Added a new config value option. If it isn't found, it will default to 1 (no change)
The option is a multiplier for the blocks-per-second travel. If you want the speedometer to show a higher value, increase this number.

The description was a bit misleading, so I changed it to a recommendation instead

You can now customize all messages!
PlaceholderAPI is now supported, so the player speed can be shown anywhere.

Options regarding having the speedometer enabled by default for everyone and toggling the speedometer has also been added.

I accidentally uploaded a fat jar containing dependencies, this one is much smaller. Both works tho.