>>You tried several times. Did you succeed at least once? :)
>
>With new batteries, it doesn't change anything. Something seems to have changed in the way the bluetooth support interacts with such device. I am back home and do not make use of it since two hours. For now, it works ok. Then, later on, I will switch back with the keyboard, with new batteries and we'll see.

I have no idea if the following has any bearing but it's an interesting discovery anyway - might be useful to you: A couple of years ago I noticed that my wireless internet connection from my laptop would, apparently at random, drop and stop working, or would work poorly. Tried everything, tested everything, but sometimes it just would stop working or work poorly. Then I discovered that it always happened when I plugged in a certain USB3 device via a multi USB extender. Cause => the device did not have a properly shielded cable and was interfering at or near the 2.4Ghz frequency. If I moved the device to the other side of the laptop then all worked fine! Intel wrote a paper about it here:

https://www.intel.com/content/www/us/en/products/docs/io/universal-serial-bus/usb3-frequency-interference-paper.html

Who knows, maybe something like this is happening?

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