@Ruarí I know what caused the problem.
Since I want to move the cache and config etc. to another disk driver, so I create a symbolic link of ~/.var/app/com.vivaldi.Vivaldi and pointed it to another location, then error occured:
~/.var/app/com.vivaldi.Vivaldi/data/vivaldi-extra-libs/media-codecs-114023/libffmpeg.so' from LD_PRELOAD cannot be preloaded (cannot open shared object file): ignored.
I do not know how to solve this if I insist wanting to change the ~/.var/app/com.vivaldi.Vivaldi folder to another disk driver.
Finally, I tried only make symbolic link of cache and config folder, and kept the data folder, things going well.
And btw, I choose to use the flatpak version because in China, vivaldi repo of debian is banned, it's annoying to update vivaldi automatically using apt without using a vpn, so I want to use the flatpak version.