I am using the most recent Eclipse IDE build id 20231201-2043 and created a barebones Maven project. However, out-of-the-box there is an error in the pom.xml file.

Problem:

Here in the pom.xml file you can see an error:

When hovering over the first error icon, the error is:

  • cvc-elt.1.a: Cannot find the declaration of element 'project'.

The second error is:

  • Downloading external resources is disabled.

Solution:

Seems to be a bug in the IDE. Simply change the URL as follows:

OLD: https://maven.apache.org/xsd/maven-4.0.0.xsd

NEW: http://maven.apache.org/xsd/maven-4.0.0.xsd