Ok, I realise it’s been a while but, for the sake of other who might hit this problem (or one like it), us Nextcloud users are generally using it because we’re security-conscious and like to keep our data private.
If you’re like me, you might have enabled 2FA which means if you enter your ‘usual’ password in your config file, you can’t then enter your second authentication method.
If this is the case, you’ll need to create a ‘one-time’ password in Nextcloud and use this instead of your ‘normal’ password. Get one by going to Nextcloud settings, Security and scroll to bottom. Hit ‘Create new app password’ and copy to the URL in the config.

Ok, thanks. Got that sorted now :)
Hopefully this will help others with the same dilemma.
I had read a post referencing the use of file://
notation which, apparently, is a red-herring.

Just for clarity to others, a local compliments.json
file should be located in /pi/MagicMirror/modules/default/compliments/ directory and referenced using only the file name in the config file.

e.g. remoteFile: 'compliments.json'

Hi…
I don’t consider myself to be a novice but setting up a remote compliments file is proving to be a real challenge.
Unfortunately, IMO the documentation isn’t that great when targetting a remote file - I’ve tried all sorts of config lines but to no avail.

e.g.

remoteFile: 'http://localhost:8080/compliments.json'
remoteFile: 'http://localhost:8080/modules/compliments.json'

for localhost, also read 127.0.0.1 and its assigned IPv4 address - I even moved the file into different directories in the vain hope it was a webserver permissions problem.

This is the (current) error in the debug window using localhost…

Access to XMLHttpRequest at 'http://localhost:8080/compliments.json' from origin 'http://0.0.0.0:8080' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
compliments.js:134
GET http://localhost:8080/compliments.json net::ERR_FAILED

Similarly, I also tried…

remoteFile: 'file://home/pi/MagicMirror/compliments.json'

ALL ATTEMPTS to target a filesystem file (compliments.json) fail :( …

compliments.js:134 GET http://0.0.0.0:8080/modules/default/compliments/file://home/pi/MagicMirror/compliments.json 404 (Not Found)

I can only assume my notation is wrong somewhere/somehow!
Incidentally, the file formatting appears to be correct so I’m convinced it’s the way I’m trying to ‘point’ the system at the json file.

If anyone can help, I’d appreciate it. Not much hair left to pull out :(

Ok, I realise it’s been a while but, for the sake of other who might hit this problem (or one like it), us Nextcloud users are generally using it because we’re security-conscious and like to keep our data private.
If you’re like me, you might have enabled 2FA which means if you enter your ‘usual’ password in your config file, you can’t then enter your second authentication method.
If this is the case, you’ll need to create a ‘one-time’ password in Nextcloud and use this instead of your ‘normal’ password. Get one by going to Nextcloud settings, Security and scroll to bottom. Hit ‘Create new app password’ and copy to the URL in the config.