ccleaner v.5.88.9346 (64bit) erased calender of Thunderbird 91.4.0

It has occured several times already.

With a new version-up of ccleaner calender contents were totally erased.

I was careful NOT to install ccleaner update soon, as I have already experienced

about 4 times before. This time, although I have waited for a moment, the bug

was not yet resolved...

Please contact our support team via the Contact Us form located here: https://support.piriform.com/hc/en-us/requests/new?ticket_form_id=86507 or by emailing support@ccleaner.com - they'll be happy to let you know what information would be needed from the CCleaner software (and possibly from Thunderbird) will be needed to investigate this issue further.