Lemon juice and Vinegar.
Using lemon juice
or vinegar can cause problems when cleaning windows. But probably not if you only use them occasionally.
Lemon juice
despite being so sour is fill of
sugar.
Which attracts insects that walk
over your clean windows looking for
sugar
to eat
and leave behind droppings. In the worst case
lemon juice
will attract ants
which can chew out your wooden window frames in search if the
sugar.
Vinegar also contains sugar
however not in the same quantity as lemon
juice.
Vinegar tends not to attract
insects
like
lemon juice however it causes other problems. Such as regularly coating raw wooden window frames in vinegar will start to dissolve the wood and leach out the natural oils. Over time vinegar will make paint or varnish on the wooden window frames porous and chalky causing the frames to need repainting or varnishing in half the usual time or less.
Vinegar on aluminium window frames will reduce the life of the finish and eventually eat right through the aluminium.
At the risk of repeating my self. If you only use lemon juice or vinegar occasionally you probably wont have any major problems.
Read why Modern inks are not good for the window cleaning process