Links are static code, while the link for the status symbol (the red X and the green checkmark) and item subject must be rendered on-the-fly.

链接是静态代码，而状态符号(红色的X及绿色的对号)链接及项目主题必须动态呈现。

youdao

So if you hold that right swiping gesture just a bit longer, the bar turns red and the checkmark turns to an x to let you know that if you let go at this point you will delete the current message.

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