As I often added opening_hours and sometimes had to search a bit on the websites. I thought why not letting Google do the searching for me ;)

Here is what I came up with. I am using this Google query:

"öffnungszeiten" OR "geschäftszeiten" OR "sprechzeiten" OR "opening hours" OR "orari" OR "orario" site:$website

and saved the query as bookmark and added a keyword to it in Firefox.

Now if I am at a website like http://example.com/ and I can not find the opening hours right away I just select the location bar with Ctrl-L, hit the right arrow key, add my keyword (“go “ for google opening hours) and hit enter …