RE: Disabling desktop mode
That said, the battery "refusing to charge" is a deliberate behavior of desktop mode. The idea is that charging a battery (and especially to 100%) reduces its long-term life, since batteries can only be charged so many times and maxing out their capacity is particularly "bad". So if you configure your battery to only charge up to 80%, for example, and also tell it to allow itself to naturally discharge down to 50% even while on AC power before it starts charging AGAIN, your battery's long-term life will increase. Obviously your battery life on a single charge will be lower (especially if you switch to battery power while it's down near 50%...), but that application detected that you tend not to spend much time running on battery and/or don't routinely come close to draining it, so it suggested that you might prefer to optimize your battery charging strategy for long-term life rather than single-charge capacity. Tesla cars actually default to only charging themselves to 80% for this exact reason. You have to manually select a "Max Range charge" mode every single time you want it to go to 100%, and they recommend against doing this on a routine basis.