Set comptext as the editor for new markdown files by creating $:/config/EditorTypeMappings/text/x-markdown and adding comptext as the content. (Thanks to Saq’s comment in a previous thread)
Edited the edit-CompText config to have the following template*: { "pattern": "[[", "filter": "[all[tiddlers]!is[system]]", "start": "[](#", "end": ")", "startOffset" : 1 }