Null key while loading dictionary of Verse.Pawn

[Pangaea]

Wrote about this issue over a month ago in Fluffy's thread, but there is no reply yet, so I'm trying here.

This is the only red line error I get, and it sounds like it's related to Fluffy's WorkTab:

Code Select Expand

Null key while loading dictionary of Verse.Pawn and WorkTab.PawnPriorityTracker. label=Priorities

When I click on that line in the game dev mode, this pop up:

Code Select Expand

Null key while loading dictionary of Verse.Pawn and WorkTab.PawnPriorityTracker. label=Priorities
Verse.Log:Error(String, Boolean)
Verse.Scribe_Collections:Look(Dictionary`2&, String, LookMode, LookMode, List`1&, List`1&)
WorkTab.PriorityManager:ExposeData()
Verse.CrossRefHandler:ResolveAllCrossReferences()
Verse.ScribeLoader:FinalizeLoading()
Verse.Game:LoadGame()
Verse.SavedGameLoaderNow:LoadGameFromSaveFileNow(String)
Verse.Root_Play:<Start>m__0()
Verse.LongEventHandler:RunEventFromAnotherThread(Action)
Verse.LongEventHandler:<UpdateCurrentAsynchronousEvent>m__1()

Do you know how it's possible to fix this?

Thankfully there doesn't seem to be a very serious problem when I play, but the top row in the WorkTab is oddly coloured, and if I try to change priorities with the scroll-wheel things get messed up in a totally different row. I wrote more about it in the linked thread above.

These are the mods that I use:
  <activeMods>
    <li>Core</li>
    <li>HugsLib</li>
    <li>AllowTool</li>
    <li>ModManager</li>
    <li>CommonSense</li>
    <li>Achtung</li>
    <li>BetterPawnControl-2.0.2</li>
    <li>Vanilla Bionics Expansion</li>
    <li>Numbers</li>
    <li>WorkTab</li>
    <li>Pharmacist</li>
    <li>PickUpAndHaul</li>
    <li>DefensivePositions</li>
    <li>MedicalTab</li>
    <li>AnimalTab</li>
    <li>WhileYoureUp</li>
    <li>RimworldSearchAgency</li>
    <li>MoreHarvestDesignators-1.0</li>
    <li>ShowDrafteesWeapon</li>
    <li>StackXXL</li>
    <li>Adaptive Cassie storyteller</li>
    <li>DontBlockDoorMod</li>
    <li>TraderDismissal</li>
    <li>RecipeIcons</li>
    <li>BionicIcons-master</li>
    <li>RF - Packed Lunches</li>
  </activeMods>