[Can fonts and other source files be 'embedded' in PNGs or JPGs?]

Thank you for the information!

[Can fonts and other source files be 'embedded' in PNGs or JPGs?]

Can fonts and other source files be 'embedded' in a PNG or JPG created from Affinity Designer? I was hoping to confirm if PNGs and JPGs are 'flattened' files and do not contain the embedded versions of the source files used to create them like PDFs can. If source files can be embedded, is there a way to prevent that from happening in Affinity Designer? I am asking due to concerns about digital assets that I want to purchase, but they restrict embedding.