Here you go, tried best to replicate the circumstances on my Thinkpad T520 (i5-5300, 8 GB RAM) running Ubuntu 22.10 and Firefox 111.0.1 (as opposed to 111.0 on the framework)
top - 10:38:06 up 15 min, 1 user, load average: 3.91, 2.67, 1.70
Tasks: 234 total, 3 running, 231 sleeping, 0 stopped, 0 zombie
%Cpu(s): 47.8 us, 16.4 sy, 0.0 ni, 35.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 7822.9 total, 144.8 free, 2949.1 used, 4729.0 buff/cache
MiB Swap: 2048.0 total, 2044.7 free, 3.2 used. 3584.4 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2553 samuel 20 0 11.7g 528636 263828 S 87.5 6.6 4:42.13 firefox
2940 samuel 20 0 2968572 506316 196676 R 75.0 6.3 4:15.20 Isolated Web Co
1782 samuel 20 0 5178952 292648 135808 S 25.0 3.7 1:42.02 gnome-shell
18 root 20 0 0 0 0 I 6.2 0.0 0:00.97 kworker/0:1-events
2132 samuel 20 0 1119892 274940 56140 S 6.2 3.4 0:13.88 snap-store
2189 samuel 20 0 842712 106000 62560 S 6.2 1.3 0:41.88 Xwayland
5430 samuel 20 0 557856 53796 41112 S 6.2 0.7 0:03.64 gnome-terminal-
6267 root 20 0 0 0 0 I 6.2 0.0 0:00.33 kworker/1:0-events
6420 root 20 0 0 0 0 R 6.2 0.0 0:03.40 kworker/2:2-events
6901 samuel 20 0 13036 4016 3280 R 6.2 0.1 0:00.02 top
1 root 20 0 169744 14588 8816 S 0.0 0.2 0:02.14 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd
3 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rcu_gp
4 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rcu_par_gp
5 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 slub_flushwq
6 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 netns
8 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/0:0H-events_highpri
10 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 mm_percpu_wq
11 root 20 0 0 0 0 I 0.0 0.0 0:00.00 rcu_tasks_kthread
12 root 20 0 0 0 0 I 0.0 0.0 0:00.00 rcu_tasks_rude_kthread
13 root 20 0 0 0 0 I 0.0 0.0 0:00.00 rcu_tasks_trace_kthread
14 root 20 0 0 0 0 S 0.0 0.0 0:00.21 ksoftirqd/0
15 root 20 0 0 0 0 I 0.0 0.0 0:01.54 rcu_preempt
16 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0
17 root -51 0 0 0 0 S 0.0 0.0 0:00.00 idle_inject/0
19 root 20 0 0 0 0 S 0.0 0.0 0:00.00 cpuhp/0
20 root 20 0 0 0 0 S 0.0 0.0 0:00.00 cpuhp/1
21 root -51 0 0 0 0 S 0.0 0.0 0:00.00 idle_inject/1
22 root rt 0 0 0 0 S 0.0 0.0 0:00.16 migration/1
23 root 20 0 0 0 0 S 0.0 0.0 0:00.15 ksoftirqd/1
25 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/1:0H-events_highpri
I did notice the web app was quite a bit slower on the thinkpad, and and the fan on thinkpad sounds calmer, so perhaps it’s just getting used to a new computer. It seems to have improved with the most recent firefox update