How to access the Markdown editor


i’d like to use the Markdown Editor, which extends the Nextcloud Editor. According to the documentation only requires the Nexcloud Editor is required. After installing it should open any .md file right in the Markdown Editor. Unfortunately I does not. I do not get any error message nor I find any error in the log.

Is there anything I am missing/overseeing?

Nextcloud version (19.0.1):
Operating system and version (Synology NAS):
Apache (2.6):
PHP version (7.3):

That’s what I like to get:


That’s what I get:

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