How to reproduce:
\- select a component
\- ungroup it
\- edit an element \(move\, size\, \.\.\.\)
\- press undo
\- the element disappears
OR
\- select a component
\- ungroup it
\- delete it \(all parts or some\)
\- press undo
\- the elements won't come back
System:
\- Mac OS 10\.14\.2
Browsers:
\- Firefox 64\.0\.2 \(64\-bit\)
\- Safari 12\.0\.2
