One final design opportunity to consider is using non-text characters, such as asterisks, periods, carets, bars, and brackets, with or without spaces between the characters. These are safe to use, no matter which font, because they exist in all fonts.
Feel free to experiment with applying colors to the entire line of symbols or to every other symbol. But be careful when using these symbols—unless you want your signature to look like 1980s ASCII art!
If you need a solid line, try a series of underline characters like this.
As you can see, there are lots of options for creating attractive signature lines without requiring the use of placed graphics files. The only limit is your imagination and a willingness to experiment with fonts, sizes, colors, and special characters.
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