Add default/placeholder text to fields

I found that in the past other users have requested the feature to add default/placeholder text to fields, I would like to argue my use case so you might add it to the user echo feature list.

We have customers who report bugs in our forum, however they provide the description of these bugs in various ways. Decoding their description sometime takes a lot of time. I would be really helpful if we can add a placeholder text, with the information we need, to the description field.

I would look something like this:

When the user starts typing in the Description field, the placeholder text should either be overwritten or deleted. Is something like this possible? I would be really helpful for us!