[BUG] Base64 encoder/decoder does not support UTF8 characters

[baobo5625]

Which tool is impacted? Example: the token generator

To Reproduce Steps to reproduce the behavior:

1. Go to 'Base64 string encoder/decoder'
2. Input: 这个链接里共有多少条规定 https://www.gov.cn/zhengce/zhengceku/2008-11/14/content_1798.htm
3. Prompt: "Invalid base64 string"

Expected behavior https://www.base64decode.org/ could work with this encoding

Screenshots If applicable, add screenshots to help explain your problem.

Configuration (please complete the following information):

• Device: [e.g. iPhone6, ]
• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Additional context Add any other context about the problem here.

[Chanzhaoyu]

same 1004

[sharevb]

Hi @baobo5625 and @CorentinTh, fixed in #905