Upon closer inspection this issue is only present when the image gallery adds to a build page that already contains another report. I have noticed this with build pages that contain both an XML Summary Display publisher report and an image gallery report, but i'm not sure if this is repeatable with other type of reports on the build page.

Code changed in jenkins
User: Bruno P. Kinoshita
Path:
pom.xml
src/main/java/org/jenkinsci/plugins/imagegallery/comparative/ComparativeArchivedImagesGallery.java
src/main/resources/org/jenkinsci/plugins/imagegallery/comparative/ComparativeImagesGalleryBuildAction/summary.jelly
src/main/resources/org/jenkinsci/plugins/imagegallery/imagegallery/ArchivedImagesGalleryBuildAction/summary.jelly
src/main/resources/org/jenkinsci/plugins/imagegallery/imagegallery/ComparativeArchivedImagesGalleryBuildAction/summary.jelly
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox.jelly
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/.Rhistory
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/colorbox.css
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/border.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/controls.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderBottomCenter.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderBottomLeft.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderBottomRight.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderMiddleLeft.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderMiddleRight.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderTopCenter.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderTopLeft.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/ie6/borderTopRight.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/loading.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/loading_background.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/css/images/overlay.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/js/jquery-1.7.2.min.js
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/colorbox/js/jquery.colorbox.js
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree.jelly
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/css/plugin.css
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/jquery.jstree.js
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/apple/bg.jpg
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/apple/d.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/apple/dot_for_ie.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/apple/style.css
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/apple/throbber.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/classic/d.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/classic/d.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/classic/dot_for_ie.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/classic/style.css
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/classic/throbber.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default-rtl/d.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default-rtl/d.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default-rtl/dots.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default-rtl/style.css
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default-rtl/throbber.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default/d.gif
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default/d.png
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default/style.css
src/main/resources/org/jenkinsci/plugins/imagegallery/stapler/jstree/js/themes/default/throbber.gif
src/main/webapp/css/colorbox.css
src/main/webapp/css/images/border.png
src/main/webapp/css/images/controls.png
src/main/webapp/css/images/ie6/borderBottomCenter.png
src/main/webapp/css/images/ie6/borderBottomLeft.png
src/main/webapp/css/images/ie6/borderBottomRight.png
src/main/webapp/css/images/ie6/borderMiddleLeft.png
src/main/webapp/css/images/ie6/borderMiddleRight.png
src/main/webapp/css/images/ie6/borderTopCenter.png
src/main/webapp/css/images/ie6/borderTopLeft.png
src/main/webapp/css/images/ie6/borderTopRight.png
src/main/webapp/css/images/loading.gif
src/main/webapp/css/images/loading_background.png
src/main/webapp/css/images/overlay.png
src/main/webapp/css/plugin.css
src/main/webapp/js/jquery-1.7.2.min.js
src/main/webapp/js/jquery.colorbox.js
src/main/webapp/js/jquery.jstree.js
src/main/webapp/js/themes/apple/bg.jpg
src/main/webapp/js/themes/apple/d.png
src/main/webapp/js/themes/apple/dot_for_ie.gif
src/main/webapp/js/themes/apple/style.css
src/main/webapp/js/themes/apple/throbber.gif
src/main/webapp/js/themes/classic/d.gif
src/main/webapp/js/themes/classic/d.png
src/main/webapp/js/themes/classic/dot_for_ie.gif
src/main/webapp/js/themes/classic/style.css
src/main/webapp/js/themes/classic/throbber.gif
src/main/webapp/js/themes/default-rtl/d.gif
src/main/webapp/js/themes/default-rtl/d.png
src/main/webapp/js/themes/default-rtl/dots.gif
src/main/webapp/js/themes/default-rtl/style.css
src/main/webapp/js/themes/default-rtl/throbber.gif
src/main/webapp/js/themes/default/d.gif
src/main/webapp/js/themes/default/d.png
src/main/webapp/js/themes/default/style.css
src/main/webapp/js/themes/default/throbber.gif
http://jenkins-ci.org/commit/image-gallery-plugin/d7da1caa0e1d9e0acf259baeec15a1747a696db8
Log:
JENKINS-22888 Use adjuncts, and prepare for compatibility with summary_report-plugin

Hi Ioannis!

The Summary Report plug-in is loading another version fo JQuery, which doesn't seem to play well with our jquery.js and colorbox.js. I *think* the sequence is:

1. we load JQuery
2. we load Colobox and get ready to use it
3. Summary Report Plug-in loads JQuery, disabling colorbox

It raised another issue, which is loading the same JavaScript file several times. We learned how to fix it during that major rewrite of uno-choice, by using adjuncts: https://github.com/jenkinsci/image-gallery-plugin/commit/d7da1caa0e1d9e0acf259baeec15a1747a696db8#diff-504a7d9bca452d02b12d9a69b4a4f0f4R2

This issue is not responsiblefor JENKINS-22888, but is fixed anyway. A simple solution would be the Summary Report Plug-in to use adjuncts as well.

The adjuncts are defined in Stapler, the Web framework used by Jenkins (created by Kohsuke). Jenkins/Stapler is able to load an adjunct only once and control it across several plug-ins.

So I believe that if the Summary Report Plug-in started using it as well, this issue would disappear.

Created https://issues.jenkins-ci.org/browse/JENKINS-30488 to report the issue to the plug-in maintainer.

If we don't hear back from him in the next weeks, I can prepare a pull request and merge it myself after a few other weeks :o)

Fixed in 1.2