Today after having been away for a couple of days, a popup window from Avast saying that URL:Mal was found started to show up on my computer. Originally I thought it only appears when I am clicking on “Login” button on my bank’s website but then it started to appear on other sites too (can’t replicate it now though). The problem occurs both on Firefox and Chrome, including incognito modes. I did both Avast and MalwareBytes scans and removed some potential threats, the problem still persists though. What can I do to identify and solve this?