Given the recent Firefox fiasco. What are the viable options for a free software browser? Can anyone point to the most promising alternatives (apart from the other corporate browser engines)?
Regarding the “fiasco”, there was an update that you may have missed which is at least a partial fix: https://blog.mozilla.org/en/products/firefox/update-on-terms...
Some could become viable in a few years, but I wouldn't count on it to "just happen". You'll still need to actively try to get your specific use cases well-supported for a while, and if not enough people do that these projects will never get there.