The antd menu icon is not displayed?

production uses antd framework, because the production intranet is not connected to the public network, the menu icon and button icon are not displayed. How to solve this problem?

Jun.17,2022

3.9.0 later antd icon uses svg. If you fully reference the old version of
that will be packaged together, you need to download its font file yourself, and then modify the global variable (modifyVars) of less icon-url to your file address

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