Remained immobile and didn’t leave yet (6,5)

I believe the answer is:

stayed still

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'remained immobile' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'didn't leave yet' is the wordplay.
'didn't leave' becomes 'stayed' (I've seen this in another clue).
'yet' becomes 'still' (synonyms).
'stayed'+'still'='STAYED STILL'

'and' acts as a link.

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I've seen this clue in the Evening Standard.

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