I started to build up one of my user tool few weeks ago.
I am not sure is there a limitation of the fonts or size of the user tool.
Because yesterday, after a long edition of my user tool, during the editing I kept saving the file, when I reopened the user tool, there are a lot of contents which I just added were gone. In the beginning I thought it might be my mistake, and I restarted to work again at the same part, however, the same thing happened. I could still save and update my content when the editing window is still on, however, when I tried to close the editing window, it asked me to update or cancel the update which I just use shortcut to save a second ago. After I close the editing window, all the things I just added were gone again. This repeated several time and till now, I couldn't add any more and adjust the user tool.
It's quite depressed that I have finished 95% of it several times, and now I still lost 20% of contents which I added.