enlarge tmp folder

Hi, I download vivaldi browser and the installation need about 1GB of space, the installation process failed because I don’t have enough space in /tmp folder.
I wondering if It’s possible to enlarge /tmp folder?

Thank’s and sorry for my english

Vivaldi requires 1G disk space?? There must be something wrong, the official deb package is less than 60M large.
How exactly did you try to install? Which source?

Would be very bad, aside from the install, if the browser would occupy that much space in /tmp, as this is by default 50% of physical RAM only and on DietPi, 50% of RAM including swap file.

Please check for other content in /tmp first to verify it is not used by other files: ls -Al /tmp && G_TREESIZE /tmp
To verify it actually has the desired size, check available RAM + swap + current size of /tmp:
free -m && df /tmp

Generally you can increase /tmp size on runtime via: mount /tmp -o size=1234M (replace 1234 with the desired size)
Permanently you can adjust /etc/fstab, find the /tmp line and replace the size value there.
But note that this is a tmpfs, so the default, 50% of RAM+swap should actually not be changed to avoid filling the RAM with /tmp only, or heavily using the swap file.