after a while and a few new maps with different modsets, i probably have found the cause for duplicate lamps and duplicate recipes, etc ...

there is one mod https://mods.factorio.com/mod/InlaidLamps which names its new lamp "flat-lamp" and not "inlaid-lamp".
there is another mod https://mods.factorio.com/mod/HighContrastLamps which names all its new lamps that have different shapes/masks "flat-lamp-xxx", but its basic lamp without a mask is named "flat-lamp" without a suffix.

thus there are two lamps with the same internal name (both show different names in game), and different recipes (one makes its lamp with one vanilla lamp, the other makes it with two vanilla lamps). because of the same name, one lamp overwrites the other, and thus both recipes have the same icon and both result in the same item being crafted :-(

since both mods have a different goal (one to enable walking on top of a bright lamp and also make the lamp look nicer than vanilla lamps; the other to offer several somewhat dimmed lamps with shapes to combine them, making status displays, or even creating shapes of letters with them) i would like to use them both.

can one or both mod authors please rename their lamp to avoid the conflict?
that's also why i copy this post to the discussions of both mods. maybe one of the authors is no longer active, or currently busy, or just waiting for 0.17 to make modifications ...

although the high contrast lamp mod was published 5 months before the inlaid lamps, IMHO it would probably be easiest if the high contrast lamps change the name of the conflicting lamp to "flat-lamp-base" or similar since it already uses a set of names which follow the pattern "flat-lamp-xxx" and only one of them has no "-xxx" suffix. and while changing the name, would it be possible/allowed to copy the functionality of the inlaid lamps, being able to walk across the somewhat larger (status) displays that are created with the high contrast lamps?
(btw: license is "public domain" for one and "MIT" for the other, thus there should be no unsolvable problem :-)

Great Anson, i will update with this correction

hint: in the meantime (during last month) there is now even at least one more mod by the same author that has lamps. it would be nice to have all the functionality of all lamps, but without having to install three or more mods (there are also colored lamps, afraid of the dark, afraid of the dark fast replaceable lamps, dectorio, and more) which can be confusing sometimes and also has more potential of causing incompatibilities.

no idea how to achieve this; but meant only as hint to let you know of possible conflicts.