129x WeakAuras/WeakAuras.lua:5222: attempt to index field '?' (a nil value)
[string "@WeakAuras/WeakAuras.lua"]:5222: in function <WeakAuras/WeakAuras.lua:5191>
[string "@WeakAuras/WeakAuras.lua"]:5248: in function `ReplacePlaceHolders'
[string "@WeakAuras/RegionTypes/Text.lua"]:234: in function <WeakAuras/RegionTypes/Text.lua:232>
[string "@WeakAuras/RegionTypes/Text.lua"]:264: in function `?'
[string "@WeakAuras/SubscribableObject.lua"]:94: in function `Notify'
[string "@WeakAuras/RegionTypes/RegionPrototype.lua"]:637: in function `?'
[string "@WeakAuras/SubscribableObject.lua"]:94: in function `Notify'
[string "@WeakAuras/RegionTypes/RegionPrototype.lua"]:843: in function <...aceWeakAuras/RegionTypes/RegionPrototype.lua:841>

Locals:
symbol = "c"
region = Frame {
 subRegionEvents = <table> {
 }
 displayText = "%c"
 yOffset = -270
 anchorPoint = "RIGHT"
 toShow = false
 cloneId = ""
 regionType = "text"
 relativePoint = "CENTER"
 color_b = 1
 color_r = 1
 color_g = 1
 text = FontString {
 }
 subRegions = <table> {
 }
 color_a = 1
 startFormatters = <table> {
 }
 xOffsetAnim = 0
 yOffsetAnim = 0
 relativeTo = WeakAurasFrame {
 }
 values = <table> {
 }
 id = "Combat Timer"
 xOffset = 340
 width = 95
 finishFormatters = <table> {
 }
 xOffsetRelative = 0
 yOffsetRelative = 0
 height = 18.028172
}
customFunc = nil
regionState = <table> {
}
regionStates = <table> {
}
useHiddenStates = false
formatters = <table> {
}
triggerNum = nil
sym = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = "attempt to index field '?' (a nil value)"
triggerState = <table> {
 Swiftmend = <table> {
 }
 Shadow Word: Pain = <table> {
 }
 PC:[BWL][Chromaggus][Bronze] Breaths = <table> {
 }
 Blessing of Freedom (Active) = <table> {
 }
 SW:[BWL][E&F] Shadow of Ebonroc = <table> {
 }
 Text • Righteous Fury = <table> {
 }
 Trinket 2 (Warlock) = <table> {
 }
 Sunfire (SoD) 2 = <table> {
 }
 Active • Aspect = <table> {
 }
 TH: Dense Weightstone = <table> {
 }
 Active • Heroic Strike = <table> {
 }
 Barkskin (Active) = <table> {
 }
 Omen Kort = <table> {
 }
 Trinket 1 (Druid) 2 = <table> {
 }
 RF:[BWL][Razorgore] Frozen Solid = <table> {
 }
 Preparation 2 = <table> {
 }
 Arcane Intellect = <table> {
 }
 Active • Sweeping Strikes = <table> {
 }
 RF:[ZG][Venoxis] Holy Fire = <table> {
 }
 TH: Flask of Supreme Power = <table> {
 }
 Shield Block = <table> {
 }
 ElvUI Target Name Strata = <table> {
 }
 Ghostly Strike 2 = <table> {
 }
 TH: Solid Dynamite = <table> {
 }
 Active • Savage Roar (SoD) = <table> {
 }
 Shadow Dance 2 = <table> {
 }
 Shaman LB Cast Time = <table> {
 }
 BT:[BWL][E&F] Ebonroc Timers = <table> {
 }
 Active • Barkskin = <table> {
 }
 CT:[BWL][Chromaggus][Bronze] Breaths = <table> {
 }
 Savage Roar (Active) = <table> {
 }
 [ZG] FojjiCore Check = <table> {
 }
 2Hand = <table> {
 }
 A:[BWL][Razorgore] Temporal Acceleration = <table> {
 }
 Type: Misc = <table> {
 }
 CP4 - Druid = <table> {
 }
 A:[ZG][Venoxis] Holy Fire = <table> {
 }
 Active • Expose Weakness (SoD) = <table> {
 }
 Ring2 Rune 13 = <table> {
 }
 Active • Rejuv = <table> {
 }
 Energy Bar - Rogue = <table> {
 }
 Lay on Hands = <table> {
 }
 Bar • Cast (Warrior) = <table> {
 }
 Ring2 Rune 6 = <table> {
 }
 RF:[ZG][Thekal] Mortal Cleave = <table> {
 }
 Active • Trap = <table> {
 }
 Paladin FoL Cast Time = <table> {
 }
 RF:[ZG][Mar'li] Drain Life = <table> {
 }
 Avenger's Shield (SoD) = <table> {
 }
 T:[BWL][Broodlord] Teleport Warn = <table> {
 }
 Wrist Rune 3 = <table> {
 }
 Frenzied Regeneration (Active) = <table> {
 }
 Skull Bash (SoD) 2 = <table> {
 }
 Charge = <table> {
 }
 Active • Nature's Swiftness (Druid) = <table> {
 }
 Lesser Healing Potion = <table> {
 }
 Void-Powered Invoker's Vambraces = <table> {
 }
 Enrage (Active) = <table> {
 }
 Feign Death Group = <table> {
 }
 Crusader Strike (SoD) = <table> {
 }
 Ring2 Rune 3 = <table> {
 }
 Active • Ice Barrier = <table> {
 }
 TH: Elixir of Demonslaying = <table> {
 }
 CT:[ZG][Hakkar] Hard Mode = <table> {
 }
 GloveHaste = <table> {
 }
 Active - Explosive Trap = <table> {
 }
 Priest Penance Channel Time = <table> {
 }
 Concussive Shot = <table> {
 }
 TH: Major Troll's Blood Potion = <table> {
 }
 Shield Wall = <table> {
 }
 Barkskin 2 = <table> {
 }
 Bestial Wrath = <table> {
 }
 Druid Wrath Cast Time = <table> {
 }
 Active • Fire Vulnerability = <table> {
 }
 Bloodthirst = <table> {
 }
 Stoneform (Active) 2 = <table> {
 }
 Moonfire (Active) = <table> {
 }
 Bar • Cast (Mage) = <table> {
 }
 TH: Target Dummy = <table> {
 }
 Ring2 Rune 15 = <table> {
 }
 Time To Die = <table> {
 }
 Barkskin = <table> {
 }
 TH: Spiced Chili Crab = <table> {
 }
 TH: Fire Protection Potion = <table> {
 }
 Conflagurate = <table> {
 }
 Wh

SavedVariables.zip is 30.4 MB so I couldn't attach it directly. I uploaded it to my personal google drive instead.

https://drive.google.com/file/d/1ZW1YzO_WZ4LWG6UTI4tu6GeOANmkS69G/view?usp=sharing

Bisect results:

report version: 2
addon version: v1.3.0
mode at print: done
bisect origin: cli
last test result: bad
Bisect took 1 out of (6-90) steps
Hints taken: 1
Addons ruled out: 43
Addons proved: 0

Narrowest set of addons that reproduces the issue:
|-- H:WeakAuras @ 5.17.5
|  |-- D:Fojji Core @ 1.4.0
|  |-- d:WeakAuras Archive @ 5.17.5
|  |-- d:WeakAuras Model Paths @ 5.17.5
|  |-- d:WeakAuras Options @ 5.17.5
|  |  |--WeakAuras Model Paths...(see above)
|  |  |-- d:WeakAuras Templates @ 5.17.5
|  |--WeakAuras Templates...(see above)
|-- E:WeakAuras Companion @ 5.1.2
|-- A:Bisector @ 1.1.2
|-- A:BugGrabber @ v11.0.1
|-- A:BugSack @ v11.0.2

Libraries:
LibCompress @ 90083
AceDBOptions-3.0 @ 15
AceConfigCmd-3.0 @ 14
AceAddon-3.0 @ 13
LibDataBroker-1.1 @ 4
LibSharedMedia-3.0 @ 8020003
AceGUISharedMediaWidgets-1.0 @ 9004
AceGUI-3.0 @ 41
LibUIDropDownMenu-4.0 @ 90135
AceConfigRegistry-3.0 @ 21
MSA-AceConfigDialog-3.0 @ 86
LibAPIAutoComplete-1.0 @ 5
AceGUI-3.0-DropDown-ItemBase @ 2000
MSA-DropDownMenu-1.0 @ 18
AceSerializer-3.0 @ 5
AceConfig-3.0 @ 3
LibDeflate @ 3
AceConfigDialog-3.0 @ 87
LibSerialize @ 1
LibSink-2.0 @ 110002
SpellRange-1.0 @ 24
LibRangeCheck-3.0 @ 26
LibDBIcon-1.0 @ 55
MSA-Tutorials-1.0 @ 14
CallbackHandler-1.0 @ 8
AceComm-3.0 @ 14
AceTimer-3.0 @ 17
LibCustomGlow-1.0 @ 20
AceDB-3.0 @ 29
LibGetFrame-1.0 @ 62