input Chinese character under yaml block（the content copy from other side）, the words will be truncate, cursor will move inside the end of block.

[PandyYang]

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  If it only exists in 3rd party themes or css, you can still report it, but please attach the theme target or the css file. We may not "fix" it, if it is caused by 3rd party themes or css styles that we cannot support.

• [x] Searched http://support.typora.io/

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Describe the bug under certain circumstances, input may exceed expectations and the program may crash. To Reproduce

• input "---" in typora
• type Return
• copy some words from vscode or other app, or this sentence
• now move your cursor under the yaml block
• input a chinese character
• now, the words truncata and the cursor move inside the yaml block end.
• repeat input one chinese character several times
• the typora will crash.

Expected behavior chinese characters can be input normally in the area below the YAML block.

Screenshots / Screencasts

Sample Markdown File 123.md

Desktop (please complete the following information): 设备名称 DESKTOP-7RRBK4I 处理器 Intel(R) Core(TM) i7-10700 CPU @ 2.90GHz 2.90 GHz 机带 RAM 32.0 GB (31.7 GB 可用) 设备 ID 89D0F513-EA71-41D2-9096-AE5E6DE70F35 产品 ID 00331-10000-00001-AA716 系统类型 64 位操作系统, 基于 x64 的处理器 笔和触控 没有可用于此显示器的笔或触控输入

Typora Version 1.7.6

Additional context noting

[baoabaob]

很烦人的问题，很久以前就存在了。

[PandyYang]

很烦人的问题，很久以前就存在了。

不知道有没有好的解决办法，我每天都写作，一打开就得先输入一个字母才能开始打字，这体验感真的太拉垮了

[QianFuv]

真实 最近也被这个小 bug 烦到了