This requires the Glossary Converter to be installed on the machine.
When you click it, you are presented with a file selection dialog, where you can select a glossary file. It is automatically converted to a termbase, which is stored in the Glossaries folder. The termbase name is the same as the glossary file name, except it obviously has the extension .sdltb. If there already is a termbase of that name, a number will be added to make it unique. Once the termbase is created, it is added to the project termbases of the selected project.
Classic example: You just imported test.xlsx, and got test.sdltb as a result. You then import test.tbx, and to avoid conflicts, test1.sdltb is generated.
Supported formats are:
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