I want to use LaTeX notes in Xournal++ on Ubuntu to annotate on .pdf. However when I click on insert a LaTeX formula, I got:
Could not find LaTeX package 'standalone'. Please install standalone (found in texlive-latex-extra) and make sure it's accessible by your LaTeX installation).
I went online to search for help and tried:
texlive-latex-extra is already the newest version (2019.202000218-1). 0 upgraded, 0 newly installed, 0 to remove and 211 not upgraded.
I tried a tlmgr install with:
$ tlmgr install standalone (running on Debian, switching to user mode!)
/usr/bin/tlmgr: unexpected return value from verify_checksum: -5
I finally went here because of the unexpected return value:
tlmgr --verify-repo=none install standalone (running on Debian, switching to user mode!)
tlmgr: Local TeX Live (2019) is older than remote repository (2020). Cross release updates are only supported with
update-tlmgr-latest(.sh/.exe) --update See https://tug.org/texlive/upgrade.html for details.
Are there other steps I am missing or am I doing it completely wrongly?