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I have a weird bug that causes this crap:

https://filestore.community.support.microsoft.com/api/images/e86b24be-f278-4a53-9719-c5319596a6a2?upload=true

There are plenty of dumb "solutions" a-la "turn it off and on" but none of them work and/or relevant, the shell apps simply refuse to cache icon for Vivaldi. I confirmed it by checking cache data at: %localappdata%\Packages\Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy\TempState\ It contains 3 binary files:

TileCache_125_3_PNGEncoded_Data.bin
TileCache_125_3_PNGEncoded_Header.bin
StartUnifiedTileModelCache.dat

For us, only TileCache_125_3_PNGEncoded_Data.bin and TileCache_125_3_PNGEncoded_Header.bin are relevant.

WHAT I KNOW

[TileCache_125_3_PNGEncoded_Data.bin] Contains raw binary PNG data in chunks, smallest chunk seems to be 1024b, padded with 0 if PNG data is smaller than chunk size. If PNG data is bigger than chunk size it is expanded by 2x i.e. becomes 2x by 1024 - 2048 and so on. Probably optimized for binary reading. Extracting all PNG data reveals it is missing exactly that one Vivaldi icon.

[TileCache_125_3_PNGEncoded_Header.bin] The layout is also fairly simple, first 40 bytes is some header/meta data, 4bytes integer at offset 12 describes amount of entries, in my case 18, but should be 19. After the header, there are entries itself, 18 entries, each 112 bytes: enter image description here

Highlighted in red are: [offset], [all chunks size], [padding size] and [height]x[width]

WHAT I DONT KNOW

The data highlighted in blue is unknown to me, but I'm fairly sure it is somehow describes the relation between cache entry and the Start Menu tile. I assume some of them might be GUIDs, especially 16bytes long ones, but quick search for these guides in Registry resulted in nothing.

Knowing how that relation works could help me to manually insert the entry and fix this shit.

Or I could reinstall whole system like a buffon, yes.

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  • my guess would be it's some kind oh a hash but you'll need to inspect the code working with this file to be sure.
    – Igor Skochinsky
    Feb 25 at 20:07
  • Yeah, I was scared about this, it is where my RE """"""""skills""""""""" die instantly.
    – KreonZZ
    Feb 25 at 21:47

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