Cannot load page scripts/styles

First of all, a big thank for such a useful & easy-to-use plugin. Really good job!
I would need some advice however.
On localhost (http), everything works like a charm.
On the live site (https), scripts & styles on the Global tab are retrieved and can be managed as expected. However, I’m unable to load any page-specific URL and constantly get a “Url cannot be loaded or you have tried to check the front page – Statuscode: 403” warning.
– I deactivated Wordfence -> no change
– Cleared browser cache and cookies -> no change
– Deleted htaccess -> no change
– All relevant page-specific directories/files permissions are set to respectively 755 and 644 on the server (had in fact only one more js file vs. global scripts list).
Would you please advice on what else should I check?
Many thanks for your help on that.