1/ Avira safe shopping/Avira browser safety (hidden)
Pros:
best blocking ability, a few features which might be helpful for some users
Cons: those extra features are useless for MT users, disable them all as soon as you install Avira, some FPs, not the lightest because it constantly scans our traffic
2/ Norton safe web (link)
Pros:
lightest of all, zero slowdown
second best blocking ability, only scans after loading the websites so no extra CPU usage. It has the most up-to-date Symantec's web protection filter
Cons: quite prone to false positives, hidden on chrome webstore for many users so it's not easy to find by usual searching
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not recommended:
- avast online security: very good phishing protection,
doesn't support download malware protection. Only good against phishing because it's designed to complement avast AV's lack of phishing protection in the older versions. Now they included phishing protection in the AV (partially)
- Bitdefender trafficlight:
heaviest of all, good phishing protection but virtually
useless against download malwares (0/10 according to my test), questionable database compared to BD's AV, not sure if it has the latest database