False Alarm of Disabled AdSense Account by Webmail Notifier?

After installing the Firefox Add-on "Webmail Notifier" (Ver. 2.9.2), I suddenly got the following message, when jumping to my AdSense account from www.blogger.com. Having done absolutely nothing for any invalid clicking for the ads on my blogs, and having received no mails from Google, I was deeply puzzled and perplexed. After trying a few more times with the same failure, suddenly I started to suspect the newly added Add-on. Because I have added the Gmail address for my AdSense account their too. When tried to with Chrome browser, I was tremendously relieved to see my AdSense again. What a surprise!

Account Disabled

Your AdSense account for this login is currently disabled. We recommend checking your email inboxes for any messages we may have sent you regarding your account status. Sometimes our messages can be caught by email filters, so please be sure to check the Bulk/Spam folders of your email accounts as well.
If your account was disabled for invalid click activity, please visit our Disabled Account FAQ for more information.
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Still no idea why AdSense is so upset with this operation though.