ID 556956 - Nuke Viewer fps indicator sometimes fails to update and starts with random rate

Problem summary
When the starting playback in Nuke's viewer, the frame rate indicator will show a random frame rate in red for the first second after which it corrects itself and shows the correct frame rate.

Also, sometimes, the playback frame rate indicator doesn't show at all and the editable frame rate field remains visible.

Customer reported version
nuke.n/a

Customer reported platform

Steps to reproduce

1) Launch Nuke

2) Create a CheckerBoard node and connect it to the Viewer

3) Press play, the frame rate number will turn red or not work at all:

Expected behaviour
For the frame rate to be consistent and always work

Actual behaviour
The framerate always starts red and sometimes doesn't work at all. 

Testing Note
If you can't reproduce the FPS indicator not appearing, try creating a new viewer. The bug is due to an uninitialized variable so it randomly happens for each new viewer.

Workaround
None

Reproduced by support
This bug has been reproduced in:
Nuke 15.0v1 - Windows 10, Rocky 9.2, macOS Monterey

Nuke 10.0v1 - Windows 10

Earliest version tested
Nuke 10.0v1 - This issue appears to be in all tested versions of the product