When you encounter panel buttons disappearing, please read

[Aebestach]

Kopernicus/Kopernicus#638 (comment)

The root cause of this problem is that the old multi-star configuration coexists with the new multi-star configuration.
This situation only occurs when switching Kopernicus versions (from versions before Kopernicus-v209 to versions after Kopernicus-v209) and the planet package contains the old multi-star configuration.

It is recommended that users should check whether the planet package contains the old multi-star configuration when updating the Kopernicus version. If it does, please delete it. If not, you can update the version normally.

If unfortunately you update the version and start the game with the old multi-star configuration, you need to modify the .sfs file to save your craft. You can contact me directly on GitHub, Discord, and BiliBili to help you.

This also applies to WDSP

导致该问题发生的根本原因是旧的多星配置和新的多星配置共存造成的。
这种情况仅发生在切换 Kopernicus 版本的时候（从 Kopernicus-v209 之前的版本切换到 Kopernicus-v209 之后的版本）且行星包中包含旧的多星配置。

建议用户在更新 Kopernicus 版本时检查行星包中是否包含旧的多星配置，若包含请删除，若不包含，则可正常更新版本。

如果不幸更新了Kopernicus 的版本并且旧多星配置仍然包含在其中旧启动游戏，则需要修改 .sfs 文件中的内容，来拯救您的存档。可以直接在GitHub、Discord、BiliBili上联系到我来帮助您。

WDSP中也适用