KO since Firefox 68.2.0 ESR

[PhilGia]

Hi, this marvelous plugin is KO with Firefox since the 68.2.0 ESR update. I'm obliged to use this ESR version.

Css style is no more applied for media 'print'

i've made lots of tests with multiple portable version :

60.7.0 ESR --> OK 67.0.1 --> KO 60.7.1 ESR --> OK 60.7.2 ESR --> OK 60.8.2 ESR --> OK 60.9.2 ESR --> OK 68.2.0 ESR --> KO 68.3.0 ESR --> KO

regards, Phil