Avoiding invisible points when using fixed style in QGIS?

Question

We often need to load measured data using predefined color style to make it simple and easy to compare layers with each other.

We have something like this:

the problem is that sometimes there are wrong data / outliers much higher than the upper class.

This results in "invisible" points in QGIS. Is there any nice way to change the style and somehow make QGIS to also display the data outside the style classes?

I mean without asking the user to reclassify the data in style settings or using a "dynamic" style (which changes all class definitions).

The only solution I have found so far is expanding the last class range to upper value like 999999 without changing the legend description.

Do you know better solution?

Answer 1

It's kind of similar solution as the one with 99999, but maybe safer in case you underestimate max value. After you set up symbology as Graduated just switch to Rule based, symbology will be preserved, and add new class where you choose Else:

You can also just type "ELSE" in Rule culomn:

Answer 2

This is some a default in QGIS. In my example is add "all other values" symbol. Its appear in the Layer styling and layers panels, but not in the attribute table or the map itself.

Once you mark this extra symbol you can delete it, with the minus key.