Mailto Paragraph <br> vs %0A (HTML)

Hi Everyone,

I’m implementing a function which generates a mail out of a HTML form (the href target of the submit button is being changed by a JS script onChange). My problem is the formatting of the Email. First I tried %0A for new paragraphs but this didn’t work on my Android Gmail. So now I use br what works perfectly fine on my Android but it doesn’t with Outlook on my PC.

I already searched a lot but couldn’t find enough information. I’d like to know, if there is a difference between different programs/devices/operating systems where you must use br or %0A? If this is the case, I thought I could implement another checkbox, which asks the user whether he uses a mobile device or a PC (for example) and then change the paragraph variable in my JS accordingly.

Thanks in advance,

Best Regards