for how long can I store homemade chocolate mousse in the fridge?
In the UK, anything longer than 3 days from production is generally deemed risky and unsaleable for commercial purposes.
For home use, if you're fridge is at the warm end of the scale /5°c 3-5 days sounds about right to me. If it's a cold fridge /2or3°c you can add a day or two onto that range. This is a slightly higher risk approach than in a commercial setting though.