I got an error trying to start a new game. Loading a save is fine, tho there are different mods and... yeah, would be hard to pinpoint what's wrong
factorio 2.0.41 - message:

Error while running event helmod::on_init()
helmod/model/Player.lua:1276: attempt to index local 'plant_prototype' (a nil value)
stack traceback:
helmod/model/Player.lua:1276: in function 'getAgriculturalRecipes'
helmod/selector/RecipeSelector.lua:119: in function 'updateGroups'
helmod/selector/AbstractSelector.lua:372: in function 'prepare'
helmod/controller/Controller.lua:137: in function 'on_init'
helmod/controller/EventController.lua:101: in function <helmod/controller/EventController.lua:99>

I also have a similar problem. But I found this error in a bug report when I was looking for a way to fix the complete lack of recipes in Helmod.

revert muluna to 1.27.3. 1.28.0 adds something which breaks hel. there is a fix pending new interface in .42

stumbled upon this too; https://github.com/Helfima/helmod/commit/0a7189e22a967980d8667b8c0d8b93e5d8be2bb5 seems to fix it (Helmod dev branch), so probably in upcoming Helmod version 2.0.17...? maybe?

I wonder if Muluna has to do something, too... was about to file a bug there, but not sure (they introduced a "tree-plant" in 1.28.0, I wonder whether that new entity is configured incompletely/incorrectly, or whether Helmod assumes something that somehow mods are not required to obey to... plant_result seems optional, so accessing plant_result maybe should be guarded... https://lua-api.factorio.com/latest/prototypes/ItemPrototype.html#plant_result)

we'll see, I guess...

Edit: ah I guess they'll do that in the next release :-) https://github.com/Helfima/helmod/blob/0a7189e22a967980d8667b8c0d8b93e5d8be2bb5/model/Player.lua#L1267

I got another error like this after rolling back the Muluna mod

---- Error ----
helmod/dialog/RecipeExplorer.lua:92: attempt to index local 'block' (a nil value)
---- Feature Flags ----
expansion_shaders:true
freezing:true
quality:true
rail_bridges:true
segmented_units:true
space_travel:true
spoiling:true
---- Mods ----
AbandonedRuins_updated_fork:1.2.0
base:2.0.41
belt-visualizer:2.0.2
CleanFloor:2.0.0
coloured-tool-icons:0.0.5
common-prototypes-graphics:0.0.1
finely-crafted-graphics:1.1.0
aai-signals:0.7.1
aai-vehicles-chaingunner:0.7.2
aai-vehicles-flame-tank:0.6.2
aai-vehicles-hauler:0.7.3
aai-vehicles-ironclad:0.7.5
aai-vehicles-laser-tank:0.7.4
aai-vehicles-warden:0.6.4
aai-zones:0.7.2
AbandonedRuins-base:0.0.2
AircraftRealism:2.0.3
alien-biomes-graphics:0.7.0
alternative-beacons:1.0.9
ArmouredBiters:1.2.1
ballistic_missile:0.1.17
bullet-trails:0.7.1
calculator-ui:2.0.1
cargo-ships-graphics:1.0.4
color_whole_train:2.0.1
Dectorio:0.13.1
elevated-rails:2.0.41
factorio-crash-site:2.0.3
fdsl:0.1.8
Flare Stack:3.0.5
flib:0.16.2
FluidMustFlow:1.4.2
helmod:2.0.14

AmAzOnKa: Try updating Helmod? You're a couple of versions behind the latest.

I should be able to get a new version of Helmod out this weekend, fixing the other issue. Factorio devs were kind enough to do a base game update already, implementing my request that will make this a lot cleaner fix! 🙂

New version of Helmod released (2.0.17). Bug should be fixed here. Note that this requires Factorio 2.0.42

can confirm, seems to work! thanks a lot for your very quick reply!

I'm not sure why this crash occurred, but I have a theory: Muluna's "Tree" item is identical to Space Age's "Tree seed," except it grows in one tick and can not be placed by an agricultural tower. I wonder if Helmod failed to start because it failed to find an automated avenue to produce this plant from. Very interesting bug.

I'm not sure why this crash occurred, but I have a theory: Muluna's "Tree" item is identical to Space Age's "Tree seed," except it grows in one tick and can not be placed by an agricultural tower. I wonder if Helmod failed to start because it failed to find an automated avenue to produce this plant from. Very interesting bug.

Helmod was assuming that any item that has a place_result of type tree would also have a plant_result defined. Trying to index plant_result caused a crash as it was nil.

In the recently released Factorio v2.0.42, the devs were kind enough to add "plant-result" as a new type of ItemPrototypeFilter. The big could have been fixed without this but it does make it a lot cleaner!