It was a combination of factors. First, Google Chrome was originally faster and lighter weight than Firefox. Second, Google used their market advantage to push

It was a combination of factors. First, Google Chrome was originally faster and lighter weight than Firefox. Second, Google used their market advantage to push Chrome via Google search and other properties. Third, Google used multiple third parties to trick end users into installing and setting Chrome as their default via dark patterns when updating or installing Avast, Adobe Flash, Java, etc. (I had to uninstall it from my mom's computer multiple times during this time period.) Fourth, Chrome focused on their developer tools and they got much better than Firefox's. Fifth, Chrome continued to improve and get faster including much better multi-process support and crash resistance while Firefox was held back by their legacy extension framework and XUL-based UI elements. Examples of paid Chrome dark pattern installs: https://imgur.com/gallery/WWZxj https://imgur.com/gallery/WWZxj