White dwarfs are generally considered to be "hot" and "dim." They are the remnants of stars that have exhausted their nuclear fuel and have shed their outer layers.
After their formation, white dwarfs can have very high surface temperatures, often exceeding 100,000 Kelvin, which makes them appear quite bright in the ultraviolet and visible spectrum. However, because they are relatively small in size compared to other stars, their overall luminosity (brightness) is not very high, resulting in them being classified as dim compared to other stars like main sequence stars or giants.
As they cool over time, they become dimmer and cooler but still remain classified primarily as "hot" initially due to their high temperatures at formation.
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