Ccleaner wiping out Xmarks settings

CCleaner for Windows CCleaner Windows Bug Reporting
1

I use Xmarks to sync my bookmarks across my 3 PCs. Since the last Firefox update (56.0.2) I had to install Xmarks differently - no longer a plugin. Now when I run Ccleaner I lose my Xmarks settings. Is there a way to prevent this from happening?

2

find where Xmarks settings live and add an EXCLUDE to CC to prevent removal.

3

find where Xmarks settings live and add an EXCLUDE to CC to prevent removal.

So far I have not been able to find where those settings are stored.

4

Finally found that the settings are stored as a cookie in FireFox. Seems like a stupid place! Select to keep the cookie that is merely a series of numbers and letters.