Can I Use an Extension Cord With an Air Compressor?

Only if the compressor manual allows it and the cord is heavy enough. A light extension cord can cause voltage drop, motor power loss and overheating.

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For the DWFP55126, DEWALT specifies 14 AWG or larger, no longer than 50 feet, with a grounded 3-wire cord. Follow your own model manual.
See 14/3 and heavier grounded extension cords

The DWFP55126 rule

DEWALT says an extension cord for this compressor must be a grounded three-wire cord, in good condition, no longer than 50 feet and 14 AWG or larger. The manual specifically says not to use 16 or 18 AWG.

Why the gauge number seems backward

In American Wire Gauge, a smaller gauge number means a thicker conductor. So 12 AWG is heavier than 14 AWG, and 10 AWG is heavier than 12 AWG.

Air hose is often the better extension

DEWALT’s manual explicitly suggests increasing reach by adding air hose instead of using an undersized electrical extension cord. That keeps the compressor close to a proper outlet while the lightweight hose goes to the work.

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Adding air hose is often the cleaner way to reach across a garage or yard.
See 50-foot air hoses

If the breaker keeps tripping

Do not solve repeated trips by installing a larger breaker or defeating protection. Check the circuit load, compressor requirements, extension cord and other devices sharing the circuit.

Sources used for this answer