Autoresponder: different text styles are sent

I think there is a bug about email sent by autoresponder!

In the mail that i receive if i try to compilate the form:

1 Some parts of the text are orange and bigger than the other parts 

2 While in the TEST email there are the blank spaces about signature and date, in the mail that i receive when i try to compilate it there aren't

I have tested your autoresponder with test mail and completing the form. I have replicated the issue on parts of the text are orange.

Screenshot of test email. On number 4, almost all texts are highlighted in orange.

Screenshot 2 autoresponder email. The orange color seems to be gone and the font is normal.

I checked your source code and it seems you have added some styles in your email content.

May we know which is the correct email content, the one with the orange text or the plain text?

We will wait for your response.