Originally, the plan was to have a playground that people can open, load any example project into it, tweak it, throw it away. You can see the Templates page has a Play button for all the templates: it loads the template into a playground and lets you play with it, instantly. Even if you are not logged in. (Those projects are then deleted after some inactivity, currently a day.)
Then there would be an Examples panel in the Toolbar, only in the Playground, with example projects that include templates, nocode examples and code examples.
Opening any example would load it into the current project as a new undo point - meaning you could click undo to restore the previous state.