The most common and most likely answer to this crossword clue is the 7 letter word TROLLED
I've seen this crossword clue in The Daily Telegraph
T
R
O
L
L
E
D
Buddy explains!
The straight part
We know that "caused bother on the internet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case caused bother on the internet = trolled.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does TROLLED mean?
TROLLED verb- To saunter.
- To trundle, to roll from side to side.
- To draw someone or something out, to entice, to lure as if with trailing bait.
- (by extension) To fish using a line and bait or lures trailed behind a boat similarly to trawling; to lure fish with bait.
- To angle for with a trolling line, or with a hook drawn along the surface of the water; hence, to allure.
- To fish in; to try to catch fish from.
- To stroll about in order to find a sexual partner.
- (to post inflammatory material so as) to attempt to lure others into combative argument for purposes of personal entertainment and/or gratuitous disruption, especially in an online community or discussion
- (by extension) To incite anger (including outside of an Internet context); to provoke, harass or annoy.
- To move circularly; to roll; to turn.
- To send about; to circulate, as a vessel in drinking.
- To sing the parts of in succession, as of a round, a catch, and the like; also, to sing loudly, freely or in a carefree way.