Color setting of file tabs is only temporary?

In the context menu of the file tabs I can set the color of the tab but it seems that this is not saved in the project settings.
After restarting PSPAD, all tabs are again without background color. Is this intended?

Hello

File tab color isn't save in project file, but in PSCache5.bin file along other individual file information. In case when Save file state in program settings / Files is enabled

File tab color can be set in highlighter settings too - in this case it's valid for highlighter files and you can make different tab color for different highlighters.