bluetooth not working

You can try a more recent version of the Linux-libre kernel and see if the support for your chipset improved: https://trisquel.info/en/wiki/update-linux-libre-kernel

Do you know what the chipset is?

If it is a USB adapter run:

lsusb

If it is built-in run:

lspci

Look for a line that reads something about bluetooth... and post it here.

For the USB adapters at least some CSR chipsets are supported in Trisquel. Keep in mind there is a huge difference in quality of the the adapters. The only ones which work reliably are more expensive adapters with some of the CSR chipsets. At least for USB dongles. Unsure about the mini pcie ones as they are always in combination with a non-free wifi ralink chipset.

I want to say there is another free software friendly bluetooth chipset for USB dongles, but for the life of me I can't remember what it is.

hello,

thanks for the tips,
but I really don't know what is a chipset.

I thought mine was built-in (because I don't plug anything from USB), but when I ran the two commands you told, I just get a Bluetooth mention for the "lsusb":

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 003: ID 0cf3:3002 Atheros Communications, Inc. AR3011 Bluetooth
Bus 001 Device 004: ID 0c45:643e Microdia