Your comments

Doesn't sound like an unreasonable request. I have had issues keeping multiple browsers on multi PC's in sync. Biggest complaint is when sync does happen, many accesses to sites to get snap-shots instead of sharing already snapped images from other access. I try to default to site pngs vs snapshots.

I used to share work/home but sync issues and delay had me stop. Haven't tried again for a long time but if sync includes snap-shots I may try again.

Find manual sync works best, replace ALL. If updates from different browser/PC not guaranteed server sync has happened. Did have issues where old, removed sites re-appeared so issues trying to remove as do not know which is current, or easily recognize duplicates...

Have not had issue syncing manually between browsers, except sync FF to FF takes a few minutes and a sync to Chrome takes +1hr with annoying pop-ups,

Not manually syncing I am totally lost, as browsers/PC's were never-ever in sync. Del link from one and it reappears, add from another and it may show up sometime.

Too me issue is not browser side, but what is cached on server. Doesn't seem auto sync is working correctly.. Not sure if Linux/Mac/W7/W10/FF/Chrome mix has impact. I haven;t tried for probably +1yr as it was too frustrating when links were not in sync.

If browser/PC(A) I delete L1 and on browser/PC(B) I add link(L2) - when sync happens I may get L2, and I may get back L1 which was deleted.

Perhaps some configurable setting to force upload/download on browser open/close would resolve. Not a pop-up but a config value. If that looks good then perhaps only specific tabs which would reduce access on open/close (a browser specific setting).