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Add buttons (past 1/2/3 days, weeks, PDF search etc.) for Google search page
< Opiniones de Google Search Extra Buttons
Alex, well, I'll use lang info from URL if it will be present. But it's need to save lang info from any storage (localStorage was cleaned by Google engine) also.
5 languages (en, fr, de, es, ru) are supported by settings of script or by navigator.language in current browser (depends of browser settings).
Add support of search for specific language
&lr=lang_ru
&lr=lang_fr
&lr=lang_de
...