Show the proper version in the project dashboard

[humitos]

The bug was introduced at

https://github.com/rtfd/readthedocs.org/pull/2944/files#diff-9a10ae0511ab8eb72096c4a0510a364eL38

Since the {% blocktrans %} was removed, the slug name was
undefined. Besides, there is no need to translate the slug, so the
first one was also removed

Fixes #3187

[humitos]

A good way to find this kind of issues if by raising an exception on debug mode, for example: https://stackoverflow.com/a/15312316/2187091

We are abusing of the default django behaviour I my opinion, that it's to render a '' if the variable is not defined inside the template: https://github.com/rtfd/readthedocs.org/blob/f93e509f1a1c33fe8040b4db06735fdb1a4876c3/readthedocs/templates/core/project_bar_base.html#L54-L73

In this example, only the tab that is active is defined.

[agjohnson]

Hah, good catch.

We are abusing of the default django behaviour I my opinion, that it's to render a '' if the variable is not defined inside the template

This looks to be unrelated, no? There's probably a better pattern here, but not important for this fix.

[humitos]

This looks to be unrelated, no? There's probably a better pattern here, but not important for this fix.

Yeah, this is unrelated to the fix. You can merge this and I can create another issue to change the approach for that specific thing.