HDR visible in GameView, but not SceneView

Here, I have a problem that has annoyed me for weeks.

As you can see, there is no HDR in Scene View. Post-Processing still works. I was searching for answers here but no solution found.

As the provided answer is partially true and is not adequate I’ll add a little bit to it.
Unity applies the settings of the Main camera (post process, hdr, etc…) to the scene view so,
your main camera which is the First camera tagget as MainCamera should have the effect you want in the scene view
or you can temporarily create a camera and tag that camera as MainCamera (there souldn’t be any other camera tagged as MainCamera) and put the effect you want to see in the scene view on that.

In the scene view tab, click the highlighted dropdown arrow above with the shiny icon. Enable post-processing.