significant speed optimisation when large amount of lines are folded
significant speed optimisation when large amount of lines are folded

notepadqq/CodeMirror,pabloferz/CodeMirror,dperetti/CodeMirror,thomasjm/CodeMirror,pabloferz/CodeMirror,hackmdio/CodeMirror,codio/CodeMirror,wingify/CodeMirror,dperetti/CodeMirror,dperetti/CodeMirror,wingify/CodeMirror,nightwing/CodeMirror,codio/CodeMirror,codio/CodeMirror,notepadqq/CodeMirror,pabloferz/CodeMirror,nightwing/CodeMirror,hackmdio/CodeMirror,nightwing/CodeMirror,notepadqq/CodeMirror,hackmdio/CodeMirror,wingify/CodeMirror,thomasjm/CodeMirror,thomasjm/CodeMirror