Tested on master: 22c38e2d8a058619e3d05534b5e830b750aa4241

Steps to reproduce:
1. Start toaster, create a new project.
2. Click on "openembedded-core" layer to access the layer details page.
3. Click on the "Delete the openembedded-core layer from your project" button.
4. Dismiss the confirmation message that appears below the page heading by clicking on the X in the top-right corner of the message.
5. Click on the "Add the openembedded-core layer to your project" button.

Expected result:
A confirmation message appears in the same place as the confirmation message you dismissed earlier.

Observed result:
All confirmation messages are suppressed until you reload the page or navigate away then back to the layer details page.