The last warning I needed was one time >10 years ago while listening to a song I really liked I just posted one of the lines from the song on facebook.

A friend of mine saw it and assumed it was a commentary on a political event that had happened that day (it wasn't) and assumed that it meant I held a certain political opinion because of this (I didn't) and then was suspicious of my claims that posting the song lyric meant nothing more than i was enjoying the song and felt like sharing.

Since then I always assume anything I reveal online will be taken out of context and held against me, if not immediately, some day...