Hi,
I'm using GS on my smartphone (Android 7) to bidirectionally sync my contacts and my calendar with Thunderbird (Linux Mint).
Now I want to upgrade my smartphone to an Android 10 custom ROM and have the following questions:
1. Do I need Gapps? If yes, would MicroG be enough?
2. I'm (probably unfoundedly) scared that after I install Android 10 and pair it with my Thunderbird, the (now empty) calendar of the smartphone is synced to Thunderbird. I guess when setting up GS on my smartphone I just choose to sync in just one direction (onto the smartphone) first and THEN swtich to biderectional again, right? (I will do a backup anyway, don't worry)
3. I always had the problem that I could not add new tasks in Thunderbird. I get the message "Please select a calendar that supports tasks". When I add a local calendar in TB it works, but not with GS calendars. Any ideas what's going on here?
Thank you!
1. Do I need Gapps?
No, GeneralSync does not depend on any Google services being present on your device.
I'm (probably unfoundedly) scared that after I install Android 10 and pair it with my Thunderbird, the (now empty) calendar of the smartphone is synced to Thunderbird.
You are correct: while your fear is unfounded, doing backups before every large change is still a good idea. 
If you follow the default setup (select "Enter pair code" on the first screen of the app setup, then enter a pair code generated on the PC and finally confirm that you trust the other device on the PC), GeneralSync will not create any empty calendars. You will end up with the phone containing the same GeneralSync calendars and address books as the PC.
If you accidentally do the first device setup again ("Get started" on the first screen of the app setup), GeneralSync might create new empty calendars on your phone. But while that new calendar might have the same name than a calendar on the PC, it is still a different calendar and thus cannot affect any events that you currently have on the PC.
I always had the problem that I could not add new tasks in Thunderbird. I get the message "Please select a calendar that supports tasks".
That's intentional: GeneralSync currently does not support tasks. Task support is a commonly requested feature and thus something I'm working on, though.
Mixing tasks and events in the same calendar will, however, never be possible: while both "GeneralSync calendars" and "GeneralSync task lists" will be displayed as a "calendar" in Thunderbird, the first will always be limited to events while the second is always limited to tasks. This is necessary for compatibility, as most other applications separate between calendars (only containing events) and task lists (only containing tasks).
I cannot give an ETA for task support yet. While I have internal test builds with full support for Thunderbird tasks, there are a lot of compatibility issues to solve to also support Outlook and some Android app (likely OpenTasks). I expect the process to take at least a few more months until I have something ready for public testing on GeneralSync's beta channel.
That, as always, perfectly answered all my questions. Thanks a lot!
Kindly inform when will the tasks be available on a GeneralSync Calender?
Welcome to the forum and thanks for your interest in GeneralSync!
Kindly inform when will the tasks be available on a GeneralSync Calender?
At the moment, it is sadly no longer certain that task support will become available at all; most development had to pause for commercial reasons.
If task support is about to launch or anything final is decided on the topic, you will hear about it in the announcement section of this forum. Feel free to subscribe to that to get all major announcements!
