I recently took a look at our site using Ahref's Site Explorer and noticed that we currently have ~1,400 broken links. Essentially, these are questions/answers that link out to pages that 404. Fixing these is certainly something we want to take care of before it gets too out of hand.
I'll be chipping away at these over time, but thought I'd post here and open up the initiative to the community. If you'd like to help out, I've created a Google Doc to keep track of this. Taking a just few minutes to fix a couple links whenever you think about it will help a lot!
^ Anyone can edit. Log and legend are in the README.
For an example of what a good fix looks like see my edits to this answer https://webmasters.stackexchange.com/a/61537/122139
Googling keywords from the broken URL is a great strategy to find replacement links e.g. example.com/search-me-on-google