Less automatically stores all the previous versions of your models. In other words, every time a team member saves a model, a new version of that model is created automatically.

Go to the folder with your model and click on the three dots to the right-hand side on the row. Click Logs and Versions. Click Versions and you will see every version of that particular model. You can also see when it was created and by who.

Click the -icon on a specific version to open up that version in a new browser window.