Français

I think of the word Silly as when somebody does something really funny, kind of in a childish kind of way. It is an endearing word, not something insulting at all. It is sometimes meant to tease that person when they did it. But it acknowledges we are not perfect, even as adults, and we all do childish things at times. So it reflects humblness on our part to admit it, that we did something 'silly.'

 Yes, it is possible to mean that you think the person really is an idiot when you call them silly, but in English, usually a much harsher word is used, like 'stupid,' 'idiot,' or 'Jerk,' or something obscene, not the word 'silly.' That is a far fetched use of the word which is really never used for such purpose.

It is also one of the Emotes the English speakers have on their instant emote bar, and I find it a shame that it is translated into something insulting to the French and feel sorry for that because no insult is intended. I may have been guilty of using it too and not knowing it was an insult. For the English speakers, it is not an insult, it is a tease if anything, and funny. It is similar to saying: 'You are being Funny!' The same way as if a Child was being funny. You are not insulting your child! You love them, and the child usually laughs a long with it.

It might be misunderstood the same way  the French use the phrase or words 'Coo coo,' or 'Cou cou,' which in English might be understood that you are calling them 'Crazy,' or yes, an idiot! Which of course, now I understand it doesn't.
 
So, hopefully this clears up some things, I beleive no insult was intended if we can all understand that.

Oddly enough albern also translates to idiot in French....

'silly' found in these entries
In the English description:
absurd - antic - asinine - boob - buffoonery - clown about - corny - daffy - daft - daft as a brush - dippy - ditsy - ditzy - dizzy - fool around - footling - frivolous - giddy - goober - goof - goof around - goof off - goofball - goofy - hokum - horse about - horse around - inane - light-minded - look foolish - loony - make a funny face - messing around - monkey business - monkeying around - nutty - play the fool - sappy - slap happy
French:
évaporé - puéril - au temps pour moi - avoir l'air fin - bébête - bécasse - bécassine - benêt - bête - bêtise - connasse - crétin - dinde - dire des âneries - faire des bêtises - niais - nice - nigaud - oie - oison - pauvre fille - polissonner - rire comme un bossu - saucisse - stupide - Suis-je bête !

silly goose n slang ([sb] foolish or childish) dinde nf
cruche nf
silly person n ([sb] foolish or childish) idiot, idiote nmf
bete adj

English French
do silly things v expr informal (act childishly) faire des bêtises loc v
The boys are always doing silly things, like trying to put dolls' clothes on the cat.
Les garçons font toujours des bêtises, comme essayer de mettre des vêtements de poupée au chat.
do silly things v expr informal (act foolishly) faire des bêtises loc v
faire n'importe quoi loc v
She's done some silly things in her time, but lying to the police? How stupid can you get!
Elle a fait des bêtises étant jeune mais mentir à la police ! C'est vraiment bête !

Here's another word that don't translate well.

Apology


excuses

noun
les excuses
apology
la excuse
excuse, apology, plea, pretext, alibi, cop
la justification
justification, substantiation, explanation, vindication, excuse, apology
la défense
defense, prohibition, vindication, conservation, championship, apology

Might be why the French don't seem to know the meaning of the word apology.

Well, at the end, everybody would explain here what was the feeling of each one. And this not a good thing?

It’s very hard to make jokes between cultures, more than courtesy. I’m human and sometimes me too I am pained because I did not understand the message or I’m hurting because I’m using, from my point of view, a neutral or friendship attitude. Nevertheless speaking as we did in that post would make each one greater than before to understand the other one.

Now maybe we need calm and get down normal animosity.

Sure that later, we could be friends, because ‘to make a beautiful diamond, we need other diamonds’. :)