There are situations when you open a page in the browser automatically run various types of media, including commercials you are not interested, and similar trash. This is quite annoying. Fortunately, the browser vendors take into account such situations and add options that disable automatic playback.
Firefox
In the address bar, enter «about: config». We confirm that we will very careful.
In the search box that appears, enter the «plugins.click_to_play».
Make a right click on this option and select from the popup menu "Switch". After that, the setting should be «true».
In order for the change to take effect, you must restart the browser.
Chrome
Go to your browser settings. At the bottom, select "Show advanced settings."
In the Open section is "Personal data" and click on the "Configure content."
Here we are looking for the section "Plugins" and also check the "Click to play".
Click "OK".
Opera
Go to your browser settings and select the tab "Advanced".
Go to the section "Content" and also check the "Enable plug-ins only on request."
Click "OK".