Some luminance sensors will only track changes over 15 minute intervals. That’s so a cloud passing over the sun doesn’t suddenly trigger a bunch of new automations. Others like Fibaro offer more choices.
The Homeseer Sensor which @ritchierich mentioned is in a different category since it’s specifically intended to catch blinking indicator lights. it says it doesn’t work with smartthings on the product page, but it was included in their official edge driver channel, so I’m not sure what’s going on with that. That would be easy, but as I said, I am concerned about the heat from the strobe.
[ST EDGE] [RELEASE] Homeseer Devices, manufacturer-provided edge drivers