Safari 16.5.1, MacOS 15.7.8 won't donload PDF files

Here i can show you how i see a (supposed pdf) bill from my phone provider. It reads "Télécharger le PDF" ie. "Download the PDF file" which is shown as the greyish zone below. and still no "Downloads" icon in the Toolbar. It is a little different with my electricity provider with displays and icon to download teh corresponding bill but this time the button has no effect. I will try to "Show Page source" when back home.

Needless to say that it all worked nicely a few weeks ago, before what i think is when the trouble began.

I have not disabled the Open "safe" item: furthermore i did not change any of the "preference items" since last upgrade, and why has the "Download" item form the Toolbar disappeared ? The link to a pdf file opens on a blank page... and that's all (i should add it happens on all pdf files, for instance from my bank account or my gas/electricity provider. Local pdf files load perfectly even while dragged to a Safari window..

Works perfectly !!! Since that last upgrade (or so do i think) i keep downloading the pdf files with my iPad then share those onto my iMac, but I would want to fix it on the iMac. I have tried to "kind of reset" Safari, moving preferences and the like of com.apple.Safari, Caches etc. to no result. Thanks

and i should add that the disappearing icon "Downloads" has reappeared in the Toolbar. I also discovered in the Websites panel of Safari Preferences a (for me) new item "Downloads" allowing or not downloading from visited web sites.

as i just replied, either from my bank account or gas/eletricity/water providers. Mac OS 15.7.8 is the last upgrade for Big Sur as my iMac (late 2014) won't upgrade a more recent Os.

Yes of course, i have mistaken with safari 15. Sorry.

Thanks a lot, this fixes it all (and i just had found a site with this "trick") though i don't really understand why.