In the “Open Project” dialogue window, there is a “Browser” option:
I think it loads from the Snap! DB (extensions db_*). Projects might use this to save your data, but most probably doesn’t store anything proper.
IIRC, it used to be that you could save projects in the browser and access them that way. Now it only shows up if there is something currently being stored in the browser, as seems to be the case for you.
The Database blocks save to your browser, but the Open Project dialogue reads from the Database, resulting in this situation happening.
If a person creates a project that uses Database, and they really love you, they can create a sub-project of sorts that contains the actual data needed for the project.
I did this a while ago with a project I never got to finish:
Inside the project
<project name="Warning">...</thumbnail>
<osdata>{"projects":{}, ...}</osdata><!--OSDATA is injected as a tag that still works for normal project loading-->
<scenes select="1">...</project>
I don’t think there would be any way for a project to automaticially import a userscript to keep a mod loaded, is there? That would be a huge security vulnerability.
Oh no, OSDATA is just the tag that my project uses for saving local data.
Besides, I don’t think that scripts can be automatically loaded, unless you have JavaScript enabled. If you know how to read the source code for Snap!, then you can find an exhaustive list of tags.