I use a toothbrush to clean mine. It’s fiddly, but it does work.

We also get it on the window seal in Winter,some great answers!

yeah either warm water and bleach and a toothbrush or get mould remover and spray that on. very quick

Vinegar awesome am going to try that out. Vinegar seems to be the cleaning product KING!

We also have an old house – mostly get mould on upstairs windows and sills. I find a mild solutions of around 1 part vinegar to 5 parts water works really well – I use paper towel to wipe on affected areas and then put straight into bin. Eucalyptus oil seeds to deter too and also smells nice – be careful with eucalyptus oil though as it can damage some surfaces.

Yeah we have an older house so might have to do it weekly!

An older house needs weekly maintenance for windows – cleaning and drying.

I clean with a window cleaner and wipe and dry.

Try with some vinegar, not diluted. Put it in in a spray bottle, spray it on the window seals and let it stand for half an hour. Then remove it with water.