Adding a TestNG Test Case file does not work in NB IDE 16

[Emma Atkinson <em...@gmail.com>]

Hello
I am using NB IDE 16 with Gradle 7.6.  In the past I have hand-crafted
TestNG Test Cases without relying on the Freemarker Templates.

I tried and failed to add a TestNG Test Case to my project as follows:

1. From the Projects tab, select the Test Packages [java] in the tree
node.
2. RMB menu New > Other ...
3  NB displays the New File Dialog.
4. Choose Unit Tests in Category
5. Select TestNG Test Case
6.  Press Next to show the next dialog headed New TestNG Test Case
7. Leave the defaults as is (they look correct)
8 Click the Finish button
9 Dialog box goes away.
10 .... nothing happens.

If I try the same with a new TestNG Test Suite and press the Finish button
the dialog box does not disappear and I notice a very fleeting error
message, which I struggle to read.  I think it says something about an spi
file.

I could not find a way to fix it myself.  Is there a fix that I can apply?

Regards