If you are updating to latest version please delete the old version and remove from Chrome before installing the update
How to install the extension on Mozilla, no need to unzip
How to install the unpacked extension in Chrome
Download the file and unzip to a new folder
Goto Chrome Settings using three dots on the top right corner.
Then Select Extensions.
You may directly open extensions using chrome://extensions
Now, Enable developer mode
Click on Load Unpacked and select your Unzip folder.
Note: You need to select the folder in which the manifest file exists. In the screenshot, we have selected the installer folder inside Unzipped folder as it is the installer folder for our extension.