How can I have +6 variables in vb font

Is the number of font variables limited to 6?!
I created 8 axes for my vb font, but I found that only 6 coordinate axes are displayed in the master tab.
I have seen many fonts that have more than 6 variables.
Are they not built with Glyphs app?

Glyphs 2 currently only supports 6 axes. More axes will be supported in a future version of the software.