Product name should be cuttedBrowser Info Environment
Something like this should fix it:
I just downloaded the latest version of core_commerce and in its db.xml the length of the prName column in the CoreCommerceProducts is 255 characters by maximum.
So, you shouldn't be able to even save product names longer than 255 characters.
I also tested this myself and I couldn't save a product name that is longer than 255 in the core_commerce add-on.
Mainio Tech Ltd.
We actually add extra stuff to the name and because of that it went over the character limit.