These are task taken from Robert Lupton comments in DM-7321 that need to be done the the firefly library. They are the issues that are exclusively on the Firefly client/server side. I am also including some comments:

• Putting up an image often generates a small image (zoom=1); a small resize of the window causes a resize. (#2) - implemented in DM-10948
• It'd be nice to have an option for a horizontal layout (cf. ds9) – displays tend to be wider than high, but the firefly (and default ds9) display is higher than wide so you lose image area. (#3) implemented in DM-10948
• In the layers display, one layer seems to be the image. Why does it have a colour and a tickbox? (#5) DM-13124
• Pixel coords are off by (0.5, 0.5) – the middle of the bottom left pixel should be (0, 0) (i.e. offset by (1, 1) from the fits standard, which assumes fortran-style 1-indexed arrays) (#7) DM-13126
• There doesn't seem to be a way to show coordinates allowing for XY0 (#8) I am not sure what this means, i will need more detail (DM-13152)
• The nice inset detail of the image doesn't show the mask planes (#11) DM-13127
• The inset detail isn't always centred on the cursor. E.g. at the lower left corner, if you put the cursor on the LL pixel, that pixel is shown at the LL of the inset, not the centre (#12) I am not sure this behavior is wrong, I need to be convinced DM-13128

• Colours for masks appear to be case sensitive (unlike at least most web standards), and illegal colours such as RED are silently ignored (#13) DM-13132
• Support a rapid stream of visualization actions, some which come before async actions complete (from slack discussion). DM-13131

More notes:

• We have talked about make another type of api html entry point that will allow for grid type layout display. We might do this as part of the QA efforts. #2 and #3 implemented in DM-10948
• #4, #9, #10 are probably on the python api side or need to be worked on both sides and need other tickets. I will works this out with David Shupe, they need separate tickets
• #6 - I don't think this is an issue, update - will solve #6 as I documented in the comment below.
  #1, #14 - already fixed as part of DM-7321

More issues:

Fast zooming + restore failed:
How to repeat:
Catalog search Gaia at m81: Got an coverage image.
Image search WISE at m81: The WISE image swapped the Gaia coverage map.
When zoomed in fast and all the way till the zoom option panel shows, clicked Restore before closed the zoom option panel, the image got lost and the error message showed:
"ZoomOptionsPopup.jsx:52 Uncaught TypeError: Cannot read property 'zoomFactor' of null
at getInitialPlotState (ZoomOptionsPopup.jsx:52)
at Array. (ZoomOptionsPopup.jsx:87)
at dispatch (createStore.js:186)
at middleware.js:86
at index.js:85
at index.js:14
at dispatch (applyMiddleware.js:45)
at PlotImageTask.js:178
at Object.dispatch (index.js:11)
at process (ReduxFlux.js:269)
"