Social media can be tricky to use at the best of times, and blunders are quite common - but, luckily, when us regular folk type something we maybe shouldn't have - we generally don't have a huge audience jumping to tell us we've slipped up.
However, when you're Taoiseach...
Mr Leo Varadkar just moments ago posted the following tweet, wishing good luck to the Boys In Green. Harmless, right?
Eagle-eyed tweeters spotted that instead of tagging the Aviva Stadium's official Twitter profile in the post, the tweet states '(tag Aviva)'.
This had lead fellow social media users to believe that the Taoiseach didn't post this himself, rather he copied and pasted it from his supposed PR team.
And thus #tagaviva is now trending. Oh dear.
However, we've decided to look on the bright side of this - showing us that even one of Ireland's most important people is indeed human, just like us.
To err is human... To forgive, unreal?