SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = 'Q0ZJ-ZSRV-JC11-Q4M0-9N3R-TW5X-3X5K-ECSK' 
  AND product_id = 107 
  AND expires_at > 1777133773 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}