Tree menu dropdown not shown
In the release 8.0 the icon to select the visibility of optional columns of a tree view does not show the the options.
Testing with the code inspector of the web navigator, I removed the property `overflow` from the following CSS code to solve the problem:
```css
.treeview > table.tree > thead > tr > th > div {
display: flex;
overflow: hidden;
}
```
issue