Sorry, I was a bit gruff and obtuse. I meant to imply that converting to CMYK is a bad idea and just going to RGB is better. I stand by that, since the colours in the file are already RGB, and I rarely have a need for CMYK Photoshop files.
To further clarify for those that may not fully understand the color modes...
Switching a color mode to CMYK is destructive in that it will reduce the color palette to the gamut available to CMYK. Switching to CMYK may introduce an unintended edit of the image. The last thing anyone would probably want to do is dull this image into CMYK.
CMYK color mode should only be used in print applications where you are limited to those 4 inks. There's no indication that this PNG is intended for print and should be converted to CMYK.
True, but since the original poster did not specify what they were going to do with the edited file, either color space is viable. And it's unlikely that the average user editing png will be troubled by the color shifts should they occur. Colors have to be well beyond the gamut edge to be troublesome and SRGB to CMYK is not that tremendous of a jump. In addition, they'll probably have a more intuitive understanding of editing color in CMYK (closer to the pigment mode of crayola crayons that we've most of us been accustomed to since pre-school) than in RGB.
You're making a lot of assumptions about the OP and apparently have not converted enough images from RGB to CMYK to not have noticed a difference. CMYK offers an extremely limited range of color.
In grade school, we are taught red, yellow and blue as primary colors with paint and crayons - - - not cyan, magenta and yellow.
Just out of curiosity I took a look at your profile and the many other answers you have provided. You might want to do the same thing. Your language comes across as arrogant, presumptive and caustic, just as it does in this response to me. You may be a lovely human being, but it sure doesn't come across in your writing.
You can also look at my profile and see how many people have awarded me points for useful responses.
I'm sorry if you are unable to interpret my responses as anything but helpful. I'm not attacking you. I am pointing out the problem with CMYK conversion. Does the fact that fewer functions are available in CMYK mode tell you that CMYK is not the ideal mode for editing images? With color profilng and CMYK preview, there are few situations where one really must dumb down an image to CMYK mode.
Let's grow up and discuss Photoshop, not your own interpersonal issues.