This is on 0.54 sources downloaded today.
I use a mix of plain text and html tags (like ) in the description of my states. When writing plain text before the the img tag in the description is is usually saved properly (in the .qfsm xml file which I post process using saxon-b), where properly means the text is stored exactly as I typed it into the description with no additional text and I can edit the text after loading teh qfsm file. If I write the img tag as first thing into the description and save that, the output will contain additional tags and when ediing the description with qfsm a gray rectangle is shown (instead of any text) as it seems the control tries to render the html content.
It seems teh spurious tags should not be generated nor stored in the qfsm output. I could try to filter that with saxon-b but editing the state machine inside qfsm also becomes impossible (cannot edit text description as only gray rectangle is rendered). I had a quick look into the sources but currently breakpoints do not work so it's hard to track down.
Ok, this is because no setTextFormat(Qt::PlainText); is called on the Q3TextEdit (e.g. in ui_StatePropertyDlg.h line 173) so that the text control tries to render html and the control also seems to add the spurious html tags when the project is saved (i.e. when the text is pulled from teh control using getDescription() on a state). Would be super cool to get a fix in build ready to be installed on windows. Not sure how to build on windows (I tested this on linux but want to run qfsm on windows, it was just easier to build it on linux).