I do not understand why this injecting js to block js is a thing. Why is there no way to just tell the browser engine not to execute any js here? if the functionality isn't there in the browser engine, why not?
I use 2 browsers, one with JS disabled and blocking everything (like 95% of the time), and second one for say "important" stuff like banking, youtube and facebook ;)
Could always rely on the Levenshtein distance. You have to be careful with similarity approaches though as you may end up filtering important messages because they are structurally similar to the unimportant message.
Just filter out logs by the file, line that generated it (i.e. that had the log statement). Even if the actual log entry changes (e.g. because of a formatted str with vars) they will always have the same source.
Bayesian filters like for emails? You mark them as important or noise and over time it will learn. These are extremely easy to put in place and you don't have to preannotate as it learns as you go.