Comment 3 for bug 1506256

A few quick questions to the proposed workaround adding a toggle button to set object "opacity:0;" to temporarily hide objects (instead of toggling visibility with "display:none") to adjust Inkscape to your personal workflow:
* What happens if you deselect the object (maybe accidentally) - you can't reselect the now invisible object easily to "toggle" on opacity (>0) again.
* What happens if the object (or multiple selected objects) currently have different levels of object opacity, and the user toggles the button on (all forced to opacity '0') and off again: where exactly does Inkscape store the 'toggled-off' opacity for the individual objects to restore it? Would this be a lossy operation (warning the user adequately each time), dropping any prior values for opacity for selected objects or do you propose that Inkscape adds a custom SVG attribute in Inkscape's namespace to every object to store the 'toggled-off' opacity value, in order to be able to restore it back at any time later (maybe in the next session)?

The new 'Objects' dialog in current trunk (for 0.92) does have a toggle button for visibility for each object, not just for layers - could this be a solution for your workflow (see attached screenshot)? It even works for multiple selected objects …

Proposing to close the proposal as is - feature to toggle visibility per object
1) exists in 'Object > Object properties' in current stable Inkscape ([x] Hide)
2) will be accessible with better UX in the new Objects dialog in future Inkscape 0.92 (with the benefit to allow users to reselect hidden objects easily again).