After big research none of answers to this question gave me satisfaction.
I needed one solution that is lightweight, is not abandonware as Tipsy (last update years ago, 63 bug fixing pull requests ignored by author) and I can use as typical tooltip as hint for form fields on hover, but also for dynamic field validation after form submit.
Really good one is as mentioned earlier PowerTip, but there is big issue with it: you can only have one tooltip visible at once. For me it's disqualification, I checked resources and this is basic assumption of author - only one tooltip at once, there is one single DOM object for all tooltips etc.
Tooltipster
After loosing another hour I found solution that is exactly what I needed: Tooltipster. It's really easy to implement (very similar to PowerTip) but it allows you to prepare and show many tooltips at once. Another advantage is fact of not using images at all, it's only js (~12k) and css.
Hope this will save many hours of research to someone.