Dibling has attracted interest from a number of Premier League clubs after scoring twice in 33 appearances during the previous campaign.
He also scored a double against Swansea City in an FA Cup third-round tie in January.
Everton have struggled to strengthen their squad this summer, with manager David Moyes saying last week the club are “running out” of time to sign players despite having money to spend.
They have brought in French striker Thierno Barry from Villarreal for £27m, midfielder Kiernan Dewsbury-Hall from Chelsea for about £28m, young left-back Adam Aznou from Bayern Munich and reserve keeper Mark Travers.
Five experienced starters, including Dominic Calvert-Lewin, Abdoulaye Doucoure and Ashley Young, left the Merseyside club at the end of the season.
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