ID 579124 - The Tracker can switch to its reference frame when adjusting a track anchor's pattern and search areas

Problem summary:
The Tracker can switch to its reference frame when adjusting a track anchor's pattern and search areas.

This impacts the behavior of Tracker functionality, such as "track_to_end".

Customer reported version:
Nuke 14.1v4

Customer reported platform:
CentOS 7

Steps to reproduce:
1) Launch Nuke and paste the following Constant node into the Node Graph:

Constant {inputs 0channels rgbcolor {{random(1,frame)} {random(2,frame)} {random(3,frame)} 1}}

2) Create a Tracker node, and set the current frame to anything other than frame 1, which is the Tracker's default reference frame.

3) In the Tracker's Properties, click the add track button.

4) Adjust the pattern and search areas of the track anchor in the Viewer, and observe how the Tracker's Zoom/Preview window will switch to frame 1:

NOTE: You may need to adjust the pattern and search areas multiple times before the issue occurs.

Expected behavior:
The Tracker node's Zoom window should only display the current frame, and not switch to the reference frame when the user resizes the track anchor.

Actual behavior:
Adjusting a Tracker's pattern and search areas can cause the input to switch between the current frame and the Tracker's reference frame.

Once the Tracker Preview is incorrectly displaying frame 1/the reference frame, using the "track_to_end" knob will cause the Tracker to begin at frame 1 instead of the current frame.

Workaround:

Deselecting the Tracker's current Track, and then reselecting it appears to resolves the problem: 

Alternatively, adding a node like a Grade after the Tracker seems to restore the Node Graph and Viewer back to the expected state.

Reproduced by Support in:

Nuke 15.0v4 - Windows 11, macOS 13 Ventura

Nuke 15.0v1 - Windows 11

Nuke 14.1v4 - Windows 11
Nuke 14.1v1 - Windows 11 

Nuke 14.0v4 - Windows 11, macOS 13 Ventura - Regression

Unable to reproduce bug in:
Nuke 14.0v3 - Windows 11, macOS 13 Ventura

Earliest version tested:
Nuke 14.0v6 - This issue doesn't appear in this version and has regressed