Loading saved session - Mapbox tiles won't load.

[Glassman]

What steps will reproduce the problem?

1. Save a session with mapbox tile and others loaded
2. Exit JOSM
3. Reopen JOSM
4. Open saved session

What is the expected result?

Expected to be back in the same configuration as when the session was saved.

What happens instead?

Everything loads properly except for the Mapbox image layer. It returns a tile message "increase tiles zoom level (change resolution) to see more detail" Changing resolution only brings up the hour glass symbox tile. See attached screen shot.

Please provide any additional information below. Attach a screenshot if possible.

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2017-03-14 19:27:54 +0100 (Tue, 14 Mar 2017)
Build-Date:2017-03-15 02:34:28
Revision:11732
Relative:URL: ^/trunk

Identification: JOSM/1.5 (11732 en) Linux Fedora release 25 (Twenty Five)
Memory Usage: 1399 MB / 7150 MB (657 MB allocated, but free)
Java version: 1.8.0_121-b14, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 3840x1080, :0.1 1920x1080
Maximum Screen Size: 3840x1080
Java package: java-1.8.0-openjdk:x86_64-1.8.0.121
VM arguments: [-agentpath:/usr/lib/abrt-java-connector/libabrt-java-connector.so=abrt=on]
Dataset consistency test: No problems found

Plugins:
+ ImportImagePlugin (33028)
+ ImproveOsm (97)
+ ImproveWay (12)
+ InfoMode (33004)
+ Mapillary (v1.4.2)
+ OpeningHoursEditor (33185)
+ alignways (33182)
+ apache-commons (32994)
+ apache-http (32699)
+ buildings_tools (33004)
+ ejml (32680)
+ ext_tools (33004)
+ geochat (33088)
+ geotools (33042)
+ jts (32699)
+ log4j (32699)
+ measurement (33088)
+ opendata (33156)
+ pbf (33165)
+ pdfimport (33004)
+ public_transport (33166)
+ reverter (33088)
+ routes (33126)
+ splinex (33160)
+ tofix (277)
+ undelete (32699)
+ utilsplugin2 (33182)
+ wikipedia (33098)

Map paint styles:
- https://josm.openstreetmap.de/josmfile?page=Styles/Sidewalks&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Surface&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Surface-DataEntry&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/AddressValidator&zip=1
- https://github.com/gmgeo/osmic-josm-style/archive/master.zip
- https://github.com/igitov/forest-josm-style/archive/master.zip
- https://josm.openstreetmap.de/josmfile?page=Styles/Landcover&zip=1
- ${HOME}/josmfile
+ ${HOME}/elemstyles.mapcss

Last errors/warnings:
- E: org.openstreetmap.josm.plugins.PluginListParseException: Failed to create plugin information from manifest for plugin 'mbtiles.jar'. Cause: org.openstreetmap.josm.plugins.PluginException: An error occurred in plugin mbtiles. Cause: java.io.IOException: invalid manifest format
- W: Old style SideButton usage for action org.openstreetmap.josm.plugins.tofix.TofixDialog$3@7efaf10b
- W: Old style SideButton usage for action org.openstreetmap.josm.plugins.tofix.TofixDialog$4@5dbaeba2
- W: Old style SideButton usage for action org.openstreetmap.josm.plugins.tofix.TofixDialog$5@49bbba14

[Glassman]

screenshot of josm edit area showing the hourglass tile from the mapbox layer