There are many topics that explain how to create a signature, but I personally advise you to read ---> https://bitcointalk.org/index.php?topic=1727100.msg17283187#msg17283187
Signatures are ultimately an attempt to create images using █░▀ ▌ ▐▄ so using pt instead of px will give better results for most browsers, although the signature may stretch a bit in browsers without the other, so the smaller and coherent the signature shape, the better results you'll get .

The best signatures are those that depend on fonts without using █, and therefore BESTCHANGE signature will be good and similar for all browsers, unlike other signatures.

As for how to draw shapes, there are tools such as ASCII art generator, but the results will be dull and not good.
For the test environment, tested it on Firefox and Chrome using^[1] and clicking on Preview instead of Post.


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