QGIS count points in polygon geometry generator

Question

This is a follow up question to this question.

I have in QGIS v3.22 two layers: polygon hex layer and points layer.

I want to count all the points that overlap with the polygon layer and display the sum of the points. This dynamic view must be generated in polygon layer Geometry Generator and the desired result must visually correspond to this image

Answer 1

1. Insert this code into Value box in the Layer Styling tab:

aggregate(
  layer:='Random points',
  aggregate:='count',
  expression:=1,
  filter:=intersects($geometry, geometry(@parent))
)

2. Replace Random points with your points layer name.
3. All data must be in one (same) projection.
4. After you add a new point you have to save the edits and update map window (for example move extent).

Result (gif animation):