1.1.0-spigot

I am using:
spigot > no MODS just plugins

Description:
When i open my map my browser console is spamming and lagging
https://prnt.sc/upcr2j
the map shows correct but is terribly slow (google Chrome)

The error spam is perfectly normal.. tiles that are not rendered, don't have a file and therefore produce a 404 ... this is expected and the web-app handles that perfectly fine. I would hide those 404-errors but there is no possible way to do so with javascript.

The error you posted in #94 EXT_frag_depth not supported means that your browser does not support a WebGL feature that is needed to improve performance/visuals ... I would assume that you have hardware acceleration disabled .. which would explain the EXT_frag_depth feature missing and the terrible performance.