[IDEA] Update the Twitter icon to new X branding

[RahulPrasadYadav]

Is your feature request related to a problem? Please describe. A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Describe the solution you'd like A clear and concise description of what you want to happen. add the new icon X Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

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I am new to contributing, can you assign me?

[arunnbabu81]

https://talk.tiddlywiki.org/t/7-steps-to-improve-the-tiddlywiki-documentation/2590

See this post in talk Tiddlywiki forum for detailed explanation about how to contribute.