make download button wide enough for helvetica #5039

This way the pricing link will not be shown for an empty hash. Which is easier to get into the config file than nil. And we can later verify the configuration to have a hash as the service_levels.

Bugfix/5664 stop email autofill

the masthead can only handle content of a limited width.

Alternatively we could make the masthead title wider and add padding on the left so it still aligns nicely with the mask. However the wider we make it the worse it looks on small width displays.

Another option would be to make the masthead contain multiple lines. However vertical aligment to the middle of 1 OR 2 lines of text is a real pain.

So I went with a super simple masthead and the Caption goes below.

use the former if you want a working email account or nil, the
latter if you want the email address associated with a given
user no matter if the user actually has an email account or not.

We should respect the users choice. We can still get their email from the user id if we really need to.

preparing for #5664 with some test improvements i ran into this issue

This commit includes a fix and the test improvements. In particular it
adds BrowserIntegrationTest#login - so there is no need to go through the signup procedure everytime you want a user to be logged in.

hide srp forms when no js is available