All players experiencing multiple, frequent "You have lost connection to the server" messages

When specifically did you see these issues? Forge was indeed having issues up through yesterday (Monday), but they’ve been fixed now, and there have been 0 reports of them today.

In addition, if you’re on FoundryVTT 0.8.6, that might be causing some of your issues.

You can also check your World Size: World Size Check
And your Modules: Trouble with Modules

To see if any of that is contributing.