GETTING MESSAGE: infection blocked avast web has blocked a threat

i get this message but have run avast full system scan and it says no infection… this message pops up ever time when i open safari… i have a macos vindinst-c (adw)
im not very technical but if someone could help me i would really appreciate it… here is a screen shot of the message i get…

Disable all browser extensions, quit, open again, see if you still get the warnings.
To find the culprit, enable one by one and test.

You do not have a virus, some extension/plugin/bar in Safari is trying to communicate to a likely malware carrying web address, the extension itself is not considered malware by avast (I would consider it malware).