Lazyload thumbnail for Isolation / Isolation缩略图延迟加载

[tianma8023]

I certify that I have first consulted (check all with "x")

我确认我已经查看了 (使用 "x" 选择)

• [x] Hexo documentation | Hexo 文档
• [x] Material theme documentation | Material 主题文档
• [x] Material theme issues | Material 主题的其它 issue

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I'm submitting a (check one with "x")

我正在申请 (使用 "x" 选择)

• [ ] bug report | 反馈一个 bug
• [x] feature request | 申请添加新的特性或功能
• [ ] support request | 请求技术支持

Hope the feature of lazyload thumbnail for Isolation can be added. / 希望 Isolation 的缩略图可以被 lazyload.