With respect to this: Restoring the exact original situation of a spatial bookmark? and this: How to Resize the Qgis Main Window from python
Q. Could a plug-in conceivably save the current state of the main QGIS window so that it could be restored later prior to navigating to a saved spatial bookmark?
It would make it much easier to add and print new layers in old projects which would be guaranteed to line up with previously printed layers. (I know that layers would align in QGIS, but I refer to the printed-out images registering correctly.)
The question could be replaced with:
Q. If I have saved a spatial bookmark for a project, how can I add a layer to that project that will be guaranteed to align with layers printed earlier?
(I had the sense from the first reference that it was not possible to completely, automatically, reconstruct the earlier window geometry at a later point. Indeed, I've now tried it and found the edge-positioning of the window to be too coarse to get perfect reconstruction.)