No restartOn Forge and NeoForge, mods download before the loader scans for them, so they load in the same launch.
Every loader generationForge 1.12.x through current, NeoForge, Fabric and Quilt, from one shared core and a thin adapter each.
Zero client configThe generated jar already carries its server's URL and token. Drop it in mods/ and it works. Fabric asks for one line of its own.
Leaves your own mods aloneDownloads land in hoppermods/, and in mods/ only on Fabric and only once you allow it. A jar HOPPER did not download is never deleted.