What criteria does Brave use to decide whether to sync a tab and display that on a sibling?

I’m so glad sync v2 is finally here and we can sync more than just bookmarks. Great work team!

The main sync feature I want to use is Open tab sync. I have 3 devices in a chain (Windows, Android phone and Android tablet). Normally, I would want to open a tab from my mobile in Windows and it seems to be the phone tabs that tend not to appear on the other devices. I’m experiencing inconsistent behaviour I am trying to get to the bottom of, I’ve tried a few different experiments to see what syncs and there is no clear pattern. I have had sync v2 enabled for some time but only in the last 2-4 weeks have I tried to actually view my synced tabs across devices.

To save a lot of typing and a long post, I want to know, as per the title, What criteria does Brave use to decide whether to sync a tab and display that on a sibling?

For example is it time based (every x seconds), event based (every time I open a tab, change app focus etc), does the tab have to be open for x seconds, does the tab have to be out of focus for x seconds, does it have to be a brand new tab, can I have too many tabs open, how long does a tab stay “recent” for etc etc. Why do some tabs seem to show and not others?

The main villain is my Windows browser. eg If I go to Settings > Sync > Manage… > I can see all 3 devices, the two android devices show last active of today, but next to This Device it says it last synced yesterday. Yet I know this is not true… I can see all the tabs from this computer in the android phone, for example. However it seems very picky about what recent tabs it shows from my phone. It might show nothing at all, or a tab i had open a while ago. Rarely the very most recent one(s).

I’ve opened brave://sync-internals/ on each device and traced what happens when I do things. I can see each device send a Commit request for Session and the other devices receive that same json in the next getUpdates response. But the tab does not necessarily appear on the history menu (windows) and/or Recent Tabs menu (android). One device might show one of the tabs but not another, the other device could show any set of tabs (or nothing at all).

(current) Brave versions
Windows = Version 1.17.75 Chromium: 87.0.4280.88 (Official Build) (64-bit)
Android Phone = 1.17.75 / 87.0.4280.88 (Samsung S20 Android 10)
Android Tab = as phone (Android 9 Kindle Fire HD8 with Brave installed via Google Play)

I have the following sync settings enabled on all 3 devices:
Bookmarks, History, Open Tabs, Passwords (I only really care about the last 2 and turned on the first 2 as part of trying to get tab sync to work)

Auto sync data is enabled on both Android devices https://support.brave.com/hc/en-us/articles/360047642371-Sync-FAQ


I’d like to know about this too. Only a small subset of my tabs from one device get listed on another device. Kinda makes the feature useless. :frowning:

Is a solution for the this in progress? Because with the last update on my pc instead of a maximum of 4 tabs between the ones opened on android i have only one of them.

I also would like to have desktop-android tab sync working.