It's pretty clear that extensions do have access to such things. If the source CODE is available then you could see what they use such access for.
Another good reason to keep such add-ons to a minimum since Norton may have no defense to information leaks via installed apps and plugins.
Bob
When installing extensions in Chrome, I get warnings before downloading, such as:
"This extension can access all data on your computer and the websites you visit," and, "This extension can access your data on all websites and your browsing history." Exactly what do these mean? Literally "all data," including encrypted passwords, private messages, etc.?
I have only installed two extensions because of this, and both were from long-known, trusted sources, but I got these warnings even with these.
Am I being overly cautious? I want to try a few other extensions.
Is there any Chrome extension that can access sensitive data on my computer, such as passwords? What about keylogging, such when I enter a password into a secure website? If so, what are the warning signs?
I run Norton AV nearly constantly, and it didn't complain when I downloaded and installed the two extensions. I haven't seen any problems, but am concerned.

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