Operating system: Windows 10
Graphics card: GTX1080Ti
Broken: 2.8 latest master
Worked: Probably never
Short description of error
The way Knife tool mode is executed makes it impossible to navigate 3D viewport in the Knife tool mode as long as navigation buttons are mapped to any other key than middle mouse button (MMB). This does not interfere with default Blender kemap, where Orbit (Rotate), Pan and Zoom viewport navigation actions are mapped to MMB, but doesn't allow viewport navigation in the other custom keymaps, including the proposed industry compatible one: https://developer.blender.org/T54963
There is no combination of settings in Knife Tool Modal Map section which would allow to solve this issue and make non-MMB based viewport navigation function in Knife tool mode.
Exact steps for others to reproduce the error
1, In factory default setup Blender, got to edit mode of the default cube, activate Knife tool using K key, and notice MMB to orbit, Shift+MMB to pan and Ctrl+MMB works.
2, Go to User Preferences, Keymap section, and in 3D View>3D View (Global)
3, Change Rotate View from Middle mouse to Alt+Left Mouse and change the action type from "Press" to "Click-Drag" (To distinguish from Alt+LMB click, which selects edge loops)
4, Change Zoom view from Ctrl+Middle Mouse to Alt+Right Mouse
5, In 3D viewport, notice that Alt+LMB and Alt+RMB work correctly to activate Viewport Rotate and Viewport Zoom respectively
6, Enter Knife tool mode, and notice that Alt+LMB and Alt+RMB do not work to Rotate or Zoom the viewport.
7, In Keymap editor, under 3D View>Knife Tool Modal Map, notice there is no possible setup to make these new navigation hotkeys work.
Result: There is no way to configure Knife Tool Modal Map so that viewport navigation in Knife Tool Mode works with any other mouse buttons than MMB.
Expected: It is possible to configure Knife Tool Modal Map so that it works with non-MMB based viewport havigation configuration.