Falkon crashes right after trying to access a website

[Mélodie]

I am using (trying to actually) Falkon in Ubuntu Cosmic. Here is what I get when trying to debug (I can just provide the message from gdb, I don't know how to read it).

***

$ gdb /usr/bin/falkon
GNU gdb (Ubuntu 8.1-0ubuntu3) 8.1.0.20180409-git
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
Type "show configuration" for configuration details.
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Reading symbols from /usr/bin/falkon...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/falkon
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffd2ead700 (LWP 7207)]
qt5ct: using qt5ct plugin
[New Thread 0x7fffc6815700 (LWP 7208)]
[New Thread 0x7fffbffff700 (LWP 7209)]
[New Thread 0x7fffbf7fe700 (LWP 7214)]
[New Thread 0x7fffbeffd700 (LWP 7215)]
[New Thread 0x7fffbe7fc700 (LWP 7216)]
[New Thread 0x7fffbdffb700 (LWP 7217)]
[New Thread 0x7fffbd7fa700 (LWP 7218)]
[New Thread 0x7fffbcff9700 (LWP 7219)]
[New Thread 0x7fff9ffff700 (LWP 7220)]
[New Thread 0x7fff9f7fe700 (LWP 7221)]
[New Thread 0x7fff9effd700 (LWP 7222)]
[New Thread 0x7fff9e7fc700 (LWP 7223)]
[New Thread 0x7fff9dffb700 (LWP 7224)]
[New Thread 0x7fff9cff9700 (LWP 7226)]
[New Thread 0x7fff9d7fa700 (LWP 7225)]
[New Thread 0x7fff7ffff700 (LWP 7227)]
[New Thread 0x7fff7f7fe700 (LWP 7228)]
[New Thread 0x7fff7effd700 (LWP 7229)]
[New Thread 0x7fff7e7fc700 (LWP 7230)]
[New Thread 0x7fff7dffb700 (LWP 7231)]
[New Thread 0x7fff7d7fa700 (LWP 7232)]
[New Thread 0x7fff7cff9700 (LWP 7233)]
Falkon: 1 extensions loaded
qt5ct: D-Bus global menu: no
qt5ct: custom style sheet is disabled
[7203:7224:0420/132909.332643:ERROR:nss_util.cc(808)] After loading Root Certs, loaded==false: NSS error code: -8018
[New Thread 0x7fff4f293700 (LWP 7236)]
[New Thread 0x7fff4d61e700 (LWP 7243)]
[Thread 0x7fff4d61e700 (LWP 7243) exited]
[New Thread 0x7fff4d61e700 (LWP 7259)]
[New Thread 0x7fff4ce1d700 (LWP 7260)]
[Thread 0x7fff4ce1d700 (LWP 7260) exited]
[New Thread 0x7fff4ce1d700 (LWP 7262)]
[New Thread 0x7fff3ee95700 (LWP 7271)]
[New Thread 0x7fff3e694700 (LWP 7272)]

Thread 20 "Chrome_InProcGp" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fff7effd700 (LWP 7229)]
0x00007fffcb614089 in ?? () from /usr/lib/x86_64-linux-gnu/dri/nouveau_dri.so
(gdb)

***

What is wrong with my install? Maybe he does not like my custom config? (I use fonts larger than the default).

Thanks for helping solve this.

Best regards,
Mélodie

[Mélodie (meets)]

Sorry, my Ubuntu version is Bionic, not Cosmic (I don't know why I wrote Cosmic?). I use Falkon 3.0.0-0ubuntu3