Fields for presets from "moreFields" get removed when editing

[BjornRasmussen]

Whenever the tags of an object change, the fields are updated on the spot. This means that when a checkbox that usually is found in the more fields section gets checked to the "unknown" value, it disappears. This also happens with several other fields that are only shown through the "add field" section then they are set to blank.

To reproduce:

1. Select an existing object that has a field filled out that usually only appears when added through the Add More Information section.
2. Set the field to the default state (the one that doesn't add any tags to the object).
3. The field will instantly disappear, making further editing of the field impossible without reapplying it through the Add More Information section.

To fix this, something should be added to the code that regenerates the sidebar when the tags are changed to make sure that it makes all fields that were visible when the object was last selected visible. This is already in place for fields that were just added, so very little code should need to be added to resolve this issue.