quick way to open and install stubborn apps in Chromium

I almost lost my mind trying to do this and finally stumbled on the answer.  Most apps are easily installed on Google Chromium but I was trying to install the Zotero extension for Chrome and could not for the life of me get it to work.  Theoretically, it was supposed to be installed simply by clicking the link to get the extension on Zotero's website, but each time I did, it would download the file to my computer, leaving me at a complete loss as to how to actually install it in Chrome.  I searched high and low and finally realized that if I could get Chrome to open the file, it would then automatically be installed.  This too took me a little while to figure out and it's super easy-- in Chrome just click Ctrl+O.  That's it.