That blinking is a good thing. That means that the bulb is running on a pre-heat starter, which gets the electrodes hot before sending full voltage through the fixture. This greatly extends the light’s lifespan. The modern “rapid start” and “instant start” starters just do the shotgun approach of forcing a ton of voltage through the tube, which succeeds in instantly starting it but also blasts off some of the emissive coating on the filaments. A tube running on one of those starters will fail a lot faster and the ends of the tubes will blacken quickly from the coating.
That blinking is a good thing. That means that the bulb is running on a pre-heat starter, which gets the electrodes hot before sending full voltage through the fixture. This greatly extends the light’s lifespan. The modern “rapid start” and “instant start” starters just do the shotgun approach of forcing a ton of voltage through the tube, which succeeds in instantly starting it but also blasts off some of the emissive coating on the filaments. A tube running on one of those starters will fail a lot faster and the ends of the tubes will blacken quickly from the coating.