It sounds like you don't have the GD extension installed. I don't use Ubuntu any longer, but I think it may be named php5-gd,...
On a debug site I would recommend uncommenting the following lines in the file settings.php.
nano sites/default/settings.php
if (file_exists(__DIR__ . '/settings.local.php')) {
include __DIR__ . '/settings.local.php';
}
In addition to adding...
How to Install Firmware in Debian Buster to Enable Wireless
This package contains the binary firmware for Intel Wireless cards
supported by the iwl3945, iwl4965, and...
ls-command: how to display the file size?
ls -lah
-l use a long listing format
-a, --all do not hide entries starting with.
-h --human-readable
When used with the -l...
There's lots of info on the net on achieving that, but I found it a bit too scattered, and had to combine instructions from...



