1.4beta: Spray tool performance very low compared to 1.3.2

Summary:

Possibly due to inkscape!5375 (merged) (single-click preview), the Spray tool works much slower than in Inkscape 1.3.2 in 1.4.x.

Steps to reproduce:

• open Inkscape
• use Spray tool

What happened?

The canvas updates only once or twice per second, the fan starts blowing, the CPU usage is much higher than in 1.3.2. Painting with the Spray tool is no longer smooth.

Recording (made some time ago, but there's no change in current 1.4.x):

https://gitlab.com/inkscape/inkscape/uploads/607d737ac53c58029b36e226a0a3cf47/vokoscreenNG-2024-03-12_16-37-12.mkv

What should have happened?

Painting with the Spray tool should be smooth.

Version info

Inkscape 1.4-beta (c3584d072e, 2024-04-30)

                      Compile  (Run)
    GLib version:     2.72.4
    GTK version:      3.24.33 (3.24.33)
    glibmm version:   2.66.2
    gtkmm version:    3.24.5
    libxml2 version:  2.9.13
    libxslt version:  1.1.34
    Cairo version:    1.16.0 (1.16.0)
    Pango version:    1.50.6 (1.50.6)
    HarfBuzz version: 2.7.4 (2.7.4)

    OS version:       Linux Mint 21.3