Comment 11 for bug 1970989

Below is the test I performed in a Qemu virtual environment.
Host : a Debian host.
Guest : Debian bookworm x86_64, LXQT, deinstalled preload and firefox-esr for light desktop.

On the guest I installed 2 flavours of the same 100.0 version of Firefox on :
- the snap : 100.0-2 (snap revision 1300) with the other required snaps (gnome-3-38-2004 0+git.1f9014a rev 99, gtk-common-themes 0.1-59-g7bca6ae rev 1519, core20 20220329 rev 1434)
- the deb package by hand from sid repository : 100.0-1.

Before starting the test, I started for the first time each flavour and I made the new page empty (no web search, no shortcut or recent activity).

I performed the below sequence with each flavour :
0. The host is up to date from the day (snap refresh, apt update), no background task expected, no other application on host and guest desktops.
1. I start AQemu.
2. I launch the virtual machine with Debian bookworm.
3. I login into the guest desktop environment.
4. I wait for roughly 60 s (stopwatch in hand).
5. I launch Firefox by the desktop menu entry and measure the start-up duration until the window appears.
6. I close Firefox and wait roughly 30s (stopwatch in hand).
7. I launch Firefox again and measure.
8. I close Firefox and wait roughly 30s (stopwatch in hand).
9. I launch Firefox again and measure.

In the case of the deb package application :
5. gives 2.5 s
7. gives 1.7 s
9. gives 1,6 s

In the case of the snap package application :
5. gives 5.9 s
7. gives 4.1 s
9. gives 4.3 s