A bunch of Oregon lighthouses exist in OSM but they don't have specific data about the signal sequence yet so they aren't displayed on this map. (an example of a sequence would be 0.5+(3.5) which means the light is shown for 0.5 seconds and eclipsed for 3.5 seconds)

From the README: "it asks the Overpass API for all elements with an seamark:light:sequence attribute"

If you run the query here you'll see that there's not any lights with sequence data in Oregon yet. https://overpass-turbo.eu/s/1fnZ

If you run a new query you can find that there are plenty of lights on the OR coast with other attributes. (try searching for: "seamark:light:character=*" for instance)

I looked at some US coast guard data and found that while most light houses have data on the colour, characteristic, and period, it's rarer to have sequence data. I think for most purposes, just knowing that there's a white light that flashes every 4 seconds is good enough. Knowing that the light flashes for 0.5 seconds is probably less needed (unless you're making a map visualization)

If you really want to see the OR lighthouses you could find and add sequence data to lighthouses in OSM. Or you could fork this and write some code to visualize the lights that have some data (like colour and period) but not sequence, by making some assumptions/default values.