Hi, thank you for your answer which explains sufficiently the cause of the problem. But I am not sure still, if I have a solution.
The zlip compression is actually enable, as recommended, to make the website faster. Disabling this feature, would mean I would make the website slow in favour to make your plugin run. For me a fast website has major priority, which as conclusion makes your plugin unsuitable for my purposes.
Is there any other solution? I am probably not the only one with this priorities…
Once again thank you for your support.