Why Firefox v. 36 opens all links from other programs in the background?

Question

Mozilla Firefox

Hello!
Today I updated Firefox to the latest stable version 36 and immediately discovered that when I tried to click on a link from any application (it all started with the QuiteRSS RSS reader, because I use it most often), the browser opens all links in the background, that is, it stopped transfer focus immediately to the opened tab.
Please tell me how to solve this problem?

Answer 1

Started Firefox in safe mode with all extensions disabled. As a result, I found out that the extension " Tab Mix Lite 4.35 " turned out to be the culprit of the "triumph ". Apparently there are compatibility issues.
Replaced the above extension with Tab Mix Plus 0.4.1.6 .

Answer 2

understand Firefox settings