There should not be a limit on the amount of lines that you can add to your Email Signature. I actually tested this out in my own portal, and was able to add a signature with 20+ lines of text and an image; I then sent myself a test email from the CRM, and the signature appeared as expected.
I would recommend trying to clear your cache, restart your browser, and try adding the signature again. Make sure to test it out after saving the changes, by sending yourself an email from the CRM. If the issue persists, feel free to send me a private message with a screenshot of any error you're seeing, or indication that the signature is not saving/not appearing on sent emails!
Thanks @ReganCarver, I saved the screenshot and deleted it because it contained personal information. I just need a screenshot of the Email section in a contact record, with no signature appearing. You can PM this to me!
Hi @ReganCarver, I want to let you know that your issue should now be resolved: your owner email should now show up as intended, same as your signature. You might need to refresh the page / log out and in to see these changes reflected. Let me know if you run into any issues!
Hi @nbugara, your question is not actually related to the original topic at hand here - this discussion was regarding difficulties with generating the email signature itself.
However, it is possible to increase/descrease the size of an image in an email signature, by simply dragging the edge of the image. You can also change the color of the text in the HTML section, though you would need to know some basic HTML in order to do so. Here is a GIF illustrating this process: