There were at least three small chests in Palais de la Cité and two in Durocas (I'm not sure of the latter), which were not shown on the map.
Only using Odin Sight revealed them. The same happened for me in Ireland, but I forgot where it was.
Why is this happening?
Hello @bielik01,
Thank you for bringing this to our attention!
Can you please demonstrate a few screenshots of this occurring including the location of the chests, so we can have a look?
Many thanks and if you have any additional questions, please let us know.
Hey there @bielik01,
Thank you for clarifying one such specific location where you can find an unmarked small chest. It would be helpful as @Ubi-Mark says if you could provide an image or video clip demonstrating this behaviour, or else just the exact map location of the chest and what it looks like at the location (you should find the chest in the same spot, but hanging open) so that we can pass these resources onto the developers.
I recall a few months ago reading a thread about some unmarked small chests in various areas in England, and encountered a couple of these myself, so I am familiar with the behaviour you're describing. I'll do my best to find out for you whether they are just extra wealth chests for the dedicated explorers among us, or if it is indeed a bug that they are not shown on the map when viewing it, when I have access to at least one image of your map / one of the opened chests in question for me to open the investigation with!
Thank you. 
@bielik01 Heya! I really appreciate the screenshot. I've made sure that this is documented and have filed the report with the Assassin's Creed team to investigate what may be happening!
@ImaginaryRuins Thank you for letting me know that you also noticed this occurring in England. Do you happen to recall any specific areas?
@cptnmorgan16
Hey there.
If it's not possible for you to provide screenshots that's fine but we'd like to submit your save file to the team for further investigation. It appears this account you're using on Discussions is not the account you're playing on, could you confirm the username of that account please? You don't need to manually submit a save file to us we can download it but please ensure your latest save file where this occurred is on the cloud. Thanks!
@SpirantCrayon22 Hey! We heard back from the team regarding this issue and the game doesn't show icons for small chests on the map. However, if you aren't seeing icons on the map for chests that are either medium chests or small cargo chests, please let me know!
@SpirantCrayon22 Hey there, apologies for any confusion.
To my knowledge, small chests contain silver or resources, whereas medium or larger chests contain wealth, ingots, or gear. The chests themselves are also different models, and the large chests require NPC assistance to open.
@azullFR Hey there, thanks for providing that detailed information! I've forwarded this to the team so they can take another look at this issue.
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