sorry to mislead you, actual exception line is 133 (I was testing on two machines and provided logs from instance where I've been trying to make changes to the file) at the following code:
132 Browser t11_frame = ActiveBrowser.Frames["T11_Frame"];
I've tried now with the latest NUnit version (188.8.131.5283) and issue has re-produced. Are there any logs that could help you find the problem?
I am performing the following steps:
1. Build QuickStarts_NUnit_CS project from command line using MSBUILD
2. Open NUnit UI and load obtained dll
3. Select FramesAction test and run it - exception occurs
Please tell me if you have any questions.