One easy way to check is to visit a browser’s content setting page and privacy policy. The privacy webpage should outline if your data is shared and why. It’s why the <a href="%(privacy)s">Firefox privacy notice</a> is easy to read and easy to find.
Lažka móžnosć, aby to pśeglědował, jo, k bokoju wopśimjeśowych nastejenjow a k pšawidłam priwatnosći woglědaś. Webbok priwatnosći měła wuwjasć, lěc se waše daty źěle a cogodla. Togodla móžośo <a href="%(privacy)s">pšawidła priwatnosći</a> lažko cytaś a lažko namakaś.