########## Begin output from Fedora 27 ##########
The following output is on Fedora 27, Oracle JDK 1.8.201, Eclipse Photon (2018-06). It is the
result of

1. eclipse
2. accept workspace in dialog box; opens to what is shown in the already sent screenshot.
3. hover on KEY_ANTIALIASING; wait for help box to appear
4. move mouse away from KEY_ANTIALIASING; problem does NOT occur
5. exit eclipse


$ export SWT_WEBKIT2=0
$ eclipse
org.eclipse.m2e.logback.configuration: The org.eclipse.m2e.logback.configuration bundle was activated before the state location was initialized.  Will retry after the state location is initialized.

(Eclipse:2492): GLib-GObject-WARNING **: gsignal.c:3492: signal name 'attributes-changed' is invalid for instance '0x7fa66c8af9c0' of type 'GtkTextViewAccessible'
org.eclipse.m2e.logback.configuration: Logback config file: /home/john/eclipse-workspace/.metadata/.plugins/org.eclipse.m2e.logback.configuration/logback.1.9.0.20180606-2036.xml
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [bundleresource://509.fwk1641931089:1/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [bundleresource://509.fwk1641931089:2/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]
org.eclipse.m2e.logback.configuration: Initializing logback

(Eclipse:2492): Gdk-WARNING **: Couldn't map window 0x7fa66db06330 as subsurface because its parent is not mapped.
$ 

########## End   output from Fedora 27 ##########