ADDITIONAL SYSTEM INFORMATION :
OS Build number: Windows 10 Enterprise 1803 (17134)
Java version: 1.8.0_191-b12, Oracle Corporation, Java HotSpot(TM) Client VM

A DESCRIPTION OF THE PROBLEM :
A user reports graphic glitches using JOSM with an old GPU (Radeon HD 6700), Windows 10 Enterprise 1803 and up-to-date AMD catalyst driver (15.20.1062.1004-150803a1-187674C).

Please add josm-found label to this bug report.

Screenshots:
- https://josm.openstreetmap.de/attachment/ticket/16847/2018-10-16%2021_07_33-JOSM.png
- https://josm.openstreetmap.de/attachment/ticket/16847/2018-10-12%2022_14_47-JOSM.png

DxDiag report:
- https://josm.openstreetmap.de/attachment/ticket/16847/DxDiag.txt

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :

The steps to reproduce the issue on his hardware are:
* Open JOSM for Windows (josm.jnlp, josm-tested.jar or Windows installer, it's the same)
* Hold the mouse anywhere to make a tooltip appear (especially in the relation edit panel with downloaded members)
* Move the mouse around to show much tooltips as possible (or wait enough, usually from 10 to 30 minutes of normal use)
* All the interface will be a mess of repeated UI

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Correct display
ACTUAL -
Glitches over all UI

FREQUENCY : often