Cliff Meyers added a comment - 2017-05-10 14:00 - edited Probably two potential causes to this issue: the background color is changed too early, or it's actually being hidden inappropriately. Note that the loading indicator is automatically shown and hidden as XHR calls are made. Files of interest: blueocean-web/src/main/resources/io/jenkins/blueocean/BlueOceanUi/index.jelly - that is where the id="loadbar" element is defined. Inline style block classes are used to set it up in its "white" state and increment itself while the page is loading. blueocean-core-js/.../LoadingIndicator - this is a simple JS object to show/hide the indicator and change the bg color. You may want to add some logging here to show/hide methods just to ensure you know when these methods are being called. blueocean-web/.../main.jsx. Once the extensions are fetched, the loadingIndicator color is switched. Assuming the reason the worm gets hidden is because the bgcolor changes too early, we could instead move the bgcolor change to a callback function that is passed to ReactDOM.render, so it happens after initial render is complete. If it disappears because it's actually being hidden, we need to look into why that is. Could be that something is making an XHR call much earlier in the lifecycle than before.