blacklist provider sites per default

[schloett]

add to blacklist upon installation Update blacklists of current installations via onUpdated:

• check if already in blacklist
• check if in whitelist

[chseifert]

I would argue against that for the following reasons:

1. Exploration: When data providers are not blacklisted, users can move from a "near" match, via the provider side (and that meta data/description) to a better match. Would support a "something like this" notion.
2. Consistency: It might not be clear that EEXCESS is working on some generall/cultural web pages and on some not (the latter ones happen to be the data provider portal page).

In any case, each page can be blacklisted manually (thus, the non-data-provider case can be manually achieved). One might think of showing a notification for the ability to blacklist. Or think of a tutorial/help page mentioning this.

[schloett]

On the help page, it is already mentioned.

[chseifert]

Then, I consider this done :)