The lines below may -or not- help ,: checked whether anything is blocked in Ghostery and the EFF’s Privacy Badger plus NoScript and Cookie Quick Manager, visiting www.mapillary.com, and logged in to www,mapillary.com/app and forum.mapillary.com .
Approached the sites with both Firefox and Edge on Windows 10
https://www.mapillary.com (the page with lots of black background, largest text : “Make better maps” :
- Ghostery shows no trackers detected ;
- Privacy Badget shows no trackers blocked ;
- NoSript : www.mapillary.com and www.fbcdn.net are allowed to run scripts.
‘Go to app’ opens Mapillary :
- Ghostery shows no trackers blocked ;
- Privacy Badger allows a.file.openstreetmap.org plus the b.file and c.file versions ;
‘returning control’ to Privacy Badger still allows the OSM background tiles to be rendered.
- NoScript : in addition to the two above www.openstreetmap.org is also allowed.
Cookie Quick Manager plugin shows nine cookies, all from mapillary.com - that includes the help. and forum. subdomains.
Final thought - from a mail server , when ‘legitimate’ messages can’t be authenticated : the time-out for their reply could be set too strict. : that would be outside your control, in addition to Mapillary this could be caused by your ISP or elsewhere along the line. Posting here would be a good way to elicit other Mac-users to report similar ; if no-one does …
Hope the issue resolves,
met vriendelijke groet (Dutch for ‘with friendly greeting’,