I love Avira. I'm licensed through 2020 for 3 PCs. But this extension is not very good.
It blocks and warns on perfectly legitimate web sites. PayPal.com is just one prominent example that I've encountered and seen other users report in their forum. There are many other examples, but I'm not interested in posting my browsing history online.
The price comparison feature is annoying, and never useful. I also find it an odd choice of features to add to a security-oriented extension. It also makes me feel spied upon, because clearly someone, somewhere is watching my online shopping.
The search result feature seems to only work with a few major search providers, such as Google and Bing. This makes the feature useless to me, because I care about my privacy. I don't use Google or Bing; I use Ixquick.com, StartPage.com, and DuckDuckGo.com.
And lately, it doesn't block or even detect any trackers at all. When it did, I found it didn't block many by default. I'm not sure if that was by design. You had to go in and manually enable blocking, AFTER the tracker already loaded and ... did its tracking. This is a terrible design. And like I said, the tracker blocking feature doesn't work at all anymore, unless the "0" I keep seeing on EVERY site is incorrect.
Remove the price comparison feature (your greedy partners can deal with it; customers should come first). Fix the tracker feature. Make it block by default. And stop blocking legitimate sites!