Here is the offending part of my script:
read -d \'\' TEXT <<\'EOF\'
Some Multiline
text that
I would like
in
a
var
EOF
echo \"$TEXT\" > ~/some/f
The -d option to read is a feature unique to bash, not part of the POSIX standard (which only specifies -r and -p options to read). When you run your script with sh on Ubuntu, it's getting run with dash, which is a POSIX shell, and not bash. If you want the script to run under bash then you should run it with bash, or give it a #!/bin/bash shebang. Otherwise, it should be expected to run under any POSIX sh.
If you run sh and then try that command, you get:
read: 1: Illegal option -d
If you do it while still in bash, it works fine.
I therefore deduce that your script is not running under bash.
Make sure that your script begins with the line:
#!/usr/bin/env bash
(or equivalent) so that the correct shell is running the script.
Alternatively, if you cannot do that (because the script is not a bash one), just be aware that -d is a bash feature and may not be available in other shells. In that case, you will need to find another way.