How to fix persistent crashes in Google backup and sync?

I have set up Google Backup and Sync to automatically synchronise certain folders on my iMac to Google Cloud both for backup and enabling sharing with other computers.

The process works well.

But one of the components, FinderSyncAPIExtension.appex, crashes regularly with a report containing the following:

Path:                  /Applications/Backup and Sync.app/Contents/PlugIns/FinderSyncAPIExtension.appex/Contents/MacOS/FinderSyncAPIExtension
Identifier:            com.google.GoogleDrive.FinderSyncAPIExtension
Version:               1.0 (1)
Code Type:             X86-64 (Native)
Parent Process:        ??? [1]
Responsible:           FinderSyncAPIExtension [58644]

...

System Integrity Protection: enabled

Crashed Thread:        0  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)
Exception Codes:       KERN_INVALID_ADDRESS at 0x000007fb606d1640
Exception Note:        EXC_CORPSE_NOTIFY

Termination Signal:    Segmentation fault: 11
Termination Reason:    Namespace SIGNAL, Code 0xb
Terminating Process:   exc handler [58644]

As far as I can tell the crash is triggered every time I save a new file to a folder that is synchronised. Also, the process seems to restart as synchronisation still seems to happen but getting a crash every time I save a file is annoying.

This has persisted across multiple MacOS versions (currently on 11.1).

I doubt this is a widespread problem and might result from a clash with some other add-in or system process but I have so far found no obvious culprit.

Any suggestions as to the cause? Or how to narrow down the likely cause?

Solution 1:

I solved this problem by turning off the option "Show file sync status icons and right click menu", in Google Backup and Sync -> Preferences -> Settings.

Solution 2:

I have the same problem. A crash is reported practically any time a file changes remotely on Google Drive and has to be synced to the local Google Drive folder.

Today I discovered that 7 copies of FinderSyncAPIExtension were running, all related to Google Backup and Sync:

/Applications/Backup and Sync.app/Contents/PlugIns/FinderSyncAPIExtension.appex/Contents/MacOS/FinderSyncAPIExtension

I killed all of them with the command:

killall -9 FinderSyncAPIExtension

After this, I expected one new instance to be automatically launched but none were. Even so, changes on Google Drive continued to be synced to my local folder, and changes to the local folder were synced to Google Drive. And there have been no crashes (so far).

I am unsure what functionality this extension is supposed to provide, but it may not be essential.