Feature: List of URLs as source

[HaleyHalcyon]

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• I have checked for similar feature requests in the project's issue tracker
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Feature Details

People (Well, me, but probabl someone else too) may want to create a sticker pack out of Web-hosted images, for example hosted on Imgur, or their own Web site. I feel like EweSticker should be able to create a sticker pack out of image URLs. (e.g. https://example.com/sticker000.webp, https://example.com/sticker001.webp, https://example.com/sticker002.webp)

Describe alternatives you've considered

I could download the images locally, but since I plan to update and tweak the images before finalizing them, I’d like to be able to send them as URLs.