You don't see what you're talking about, the up arrow, the default app icon will be displayed inside and you can drag it into the fold area.

Oh man. You don't understand the problem. I know how it works. See the distance between them, right after starting the application...

The first time both arrows are too close to each other. Only when you expand the hidden icons menu does the distance change and look good. Watch the video again.

First run docked app. After logging in, running, whatever (see space)

After unfolding (see space)

The user means when a new icon is added to the dock, the application tray is not correct displayed and too close to the nearby icon. Only when you expand the hidden icons menu does the distance change and look good.

用户的意思是托盘上出现新图标后，上拉箭头离右边的图标太近了，没有正确显示。只有把托盘图标展开一遍后两个图标之间的间距才恢复正常。

Oh, you mean the two ICONS are too close together when the icon is folded?
This one is currently designed that way, and later on it may be considered to provide personalization capabilities that allow the app icon or the fold icon not to be displayed, because it has a small area so the fold will be very close to you

The other two ICONS are too close together or even overlap. It's a BUG

Hello! This issue has been reported to the development team for fixing.