Download /var/log/syslog

This is fresh install of Opera 88.0 on a fresh install of Linux Mint 20.3 Cinnamon (5.4.0-91-generic). No extensions or anything.

On some websites it begins to load the system up to full stop of response.
It does not relate to any specific website.
You can always see kswadp0 process taking all the CPU.
After some time it comes back to normal, but than happens again.
Please see excerpt from kernel message buffer attached.

I have tried version 77.0 and have noticed the same issue.
Before I had Mint 18 Sara and the issue was not present.
But on Mint 20 no other application or browser caused the problem.

It worked finally just after rebooting the system (v.84)

Hangs silently for the latest 88 version, hangs with an error for 84 version.

Description:	Linux Mint 20.3
Release:	20.3
Codename:	una

light@brahmand:~/Downloads$ opera --version
84.0.4316.42

light@brahmand:~/Downloads$ opera
[75766:75766:0609/215936.355882:ERROR:sandbox_linux.cc(377)] InitializeSandbox() called with multiple threads in process gpu-process.

light@brahmand:~/Downloads$ dpkg-query -W |grep -Ei "libva|vdpau|va-dr"
i965-va-driver:amd64	2.4.0-0ubuntu1
intel-media-va-driver:amd64	20.1.1+dfsg1-1
libva-drm2:amd64	2.7.0-2
libva-wayland2:amd64	2.7.0-2
libva-x11-2:amd64	2.7.0-2
libva2:amd64	2.7.0-2
libvariable-magic-perl	0.62-1build2
libvdpau1:amd64	1.3-1ubuntu2
mesa-va-drivers:amd64	21.2.6-0ubuntu0.1~20.04.2
mesa-vdpau-drivers:amd64	21.2.6-0ubuntu0.1~20.04.2
va-driver-all:amd64	2.7.0-2

$  ls /usr/lib/x86_64-linux-gnu/dri
d3d12_dri.so  i965_dri.so        iris_dri.so        nouveau_drv_video.so  r300_dri.so        radeon_dri.so          swrast_dri.so      zink_dri.so
i830_dri.so   i965_drv_video.so  kms_swrast_dri.so  nouveau_vieux_dri.so  r600_dri.so        radeonsi_dri.so        virtio_gpu_dri.so
i915_dri.so   iHD_drv_video.so   nouveau_dri.so     r200_dri.so           r600_drv_video.so  radeonsi_drv_video.so  vmwgfx_dri.so

$ dpkg -S i965_dri.so
libgl1-mesa-dri:amd64: /usr/lib/x86_64-linux-gnu/dri/i965_dri.so

$ ls -l /usr/lib/x86_64-linux-gnu/opera
total 219652
-rw-r--r-- 1 root root   4703201 Mar 16 00:16 headless_lib.pak
-rw-r--r-- 1 root root  10308288 Mar 15 23:46 icudtl.dat
-rw-r--r-- 1 root root    233168 Mar 16 00:27 libEGL.so
-rw-r--r-- 1 root root   1860112 Mar 16 00:27 libffmpeg.so
-rw-r--r-- 1 root root   5713600 Mar 16 00:27 libGLESv2.so
-rw-r--r-- 1 root root   4107016 Mar 16 00:27 libvk_swiftshader.so
-rw-r--r-- 1 root root    545616 Mar 16 00:27 libvulkan.so.1
drwxr-xr-x 2 root root      4096 Jun  9 21:43 localization
-rwxr-xr-x 1 root root 171428336 Mar 16 00:27 opera
-rw-r--r-- 1 root root    786965 Mar 16 00:02 opera_100_percent.pak
-rw-r--r-- 1 root root    859962 Mar 16 00:02 opera_125_percent.pak
-rw-r--r-- 1 root root    937957 Mar 16 00:02 opera_150_percent.pak
-rw-r--r-- 1 root root   1285151 Mar 16 00:02 opera_200_percent.pak
-rw-r--r-- 1 root root    996888 Mar 16 00:02 opera_250_percent.pak
-rwxr-xr-x 1 root root   4642928 Mar 16 00:27 opera_autoupdate
-rw-r--r-- 1 root root     14004 Mar 15 23:45 opera_autoupdate.licenses
-rw-r--r-- 1 root root         6 Mar 15 23:45 opera_autoupdate.version
-rwxr-xr-x 1 root root    907008 Mar 16 00:27 opera_crashreporter
-rw-r--r-- 1 root root  14288462 Mar 16 00:16 opera.pak
-rwsr-xr-x 1 root root    221680 Mar 16 00:27 opera_sandbox
drwxr-xr-x 4 root root      4096 Jun  9 21:43 resources
-rw-r--r-- 1 root root    351040 Mar 16 00:14 snapshot_blob.bin
drwxr-xr-x 2 root root      4096 Jun  9 21:43 swiftshader
-rw-r--r-- 1 root root    671752 Mar 16 00:15 v8_context_snapshot.bin
-rw-r--r-- 1 root root       107 Mar 15 23:51 vk_swiftshader_icd.json

Tried

apt-get install intel-media-va-driver-non-free

-- no difference