Extract correct URL and remove Facebook warning & tracking

[Enkidu70]

This is a special case, I think. Léon is not able to handle this kind of FB redirect to external link URL:

https://m.facebook.com/flx/warn/?u=https%3A%2F%2Fwww.focus.de%2Fgesundheit%2Fratgeber%2Fapotheker-warnt-vor-natuerlichem-antibiotikum-wer-es-nimmt-wird-zum-schlumpf-91fca548.html%3Ffbclid%3DIwZXh0bgNhZW0CMTEAc3J0YwZhcHBfaWQMMzUwNjg1NTMxNzI4AAEeJJ4U1iY04LKeknOI58w3czBdQECMoGyKXS6rGaT8urwE53c73uUMH6zYdKc_aem_rHr5SbyaWkdVG0cHPQYr4g&h=AT3cDUVol511LB_DioYWzyRaZ7XpHvTfhDxNiKTfUH5GKkFYsJiWaLhWIsERxwPuoyLqG-e6fyHnYBoMgtU0Z-u5ePXLykEkA9gjN5klYbAqaN14w23Ll_MQU7aXmZLQTIfdiLsfmlVcLPxqV4Rt1r2msm4MLK3h&_rdr

It would be great to extract the real destination, which itself was added as parameter.

Tnx in advance,
Enkidu