The most common and most likely answer to this crossword clue is the 4 letter word SUDS
I've seen this crossword clue in Independent
S
U
D
S
More clues leading to the result SUDS
- Product of soap operas, you would guess? Only EastEnders
- Bubbles beginning to seep under walls of dungeons
- Foam starts to unsettle deckhand aboard ship
- Bubbly stuff from South of France sommelier’s opening
- Day overshadowed by dodgy American beer
- American beer’s unexplained demise
- They’re often found in a lather
- Froth from south of France, latest from Cannes
- Initially sullen until dad supplies beer
Buddy explains!

The straight part
We know that "Bubbles" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bubbles = suds.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 SUDS mean?
SUDS noun- Lather; foam or froth formed by mixing soap and water.
- Beer
- To cover with, or as if with, soapsuds.