linkedin cares a lot about preventing people from changing how people view their website, and they have very effective DOM detection code which watches for manipulation like this. So if you use this extension it's very likely that your account will be shadowbanned, meaning you won't show up in searches (e.g. if you are a job seeker you'll stop getting cold outreach from recruiters), your posts will be less visible or invisible if you have any, and whatever other arbitrary restrictions linkedin's algorithm puts on your account which might even include stifling normal communication from your connections. And if you don't care about any of those things you might be better off without linkedin in the first place.