When editing Variables and Abbreviations in Language Resource Template in Trados 2021, both variables and abbreviations can be exported to and imported from TXT file. Please correct me if I'm wrong. 

Given that, I tried to assemble a list of product names as variables in the TXT file, and imported it into the language resource template of my existing TM. Once done, Trados 2021 prompted me to upgrade the TM, which I did. But once the upgrade is done, I go into the Language Resource of the TM, only to find that the variable list does NOT contain any of the entries in my TXT file. I tried the same for the Abbreviations and it's the same result. Import of TXT was successful and followed by upgrade of the TM, but once upgrade was done, I went into the Abbreviation list of the language resource settings of the TM and no entry from my TXT file was there. 

I then tried to use the app called Apply TM template to do the same, by creating a new language resource template, importing my TXT files for both Variables and Abbreviations into the template. Then use this app to apply the template to other TMs. The result was the same, as the template has been successfully applied to those TMs followed by TM upgrade. Yet when the upgrade was done, I still found nothing in both Variables and Abbreviations lists of the language resource settings of those TMs. 

Can anyone help explain?