missing icon

please help, why this icon disappears

https://imgur.com/a/4mP3ZXo

My guess would be that the font has failed to load.

so what should i do now, which file should I check, app.min ?, load.js ?

You should check browser developer console.

ok, i already check : there are so many eror, when i open the console.
https://imgur.com/a/RjYm8Ig

i can see the icon now, but why there is still more error :
https://imgur.com/a/5jAVA3a

i check again, do and do again, the error is just one now :
https://imgur.com/a/WosUg42