reported error attempt to perform arithmetic on local 'fx' (a nil value)

[mooreatv]

Message: Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:164: attempt to perform arithmetic on local 'fx' (a nil value)
Time: Thu May 13 18:51:49 2021
Count: 1
Stack: Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:164: attempt to perform arithmetic on local 'fx' (a nil value)
Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:164: in function `calcCorners'
Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:174: in function `setSizeToChildren'
Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:101: in function `Snap'
Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:1422: in function `RestorePosition'
Interface\AddOns\DynamicBoxer\DBoxUI.lua:731: in function `AddTeamStatusUI'
Interface\AddOns\DynamicBoxer\DynamicBoxer.lua:237: in function `ManualExtendTeam'
Interface\AddOns\DynamicBoxer\DynamicBoxer.lua:259: in function `ManualSetup'
Interface\AddOns\DynamicBoxer\DynamicBoxer.lua:333: in function `ReconstructTeam'
Interface\AddOns\DynamicBoxer\DBoxClassic.lua:636: in function `Join'
Interface\AddOns\DynamicBoxer\DBoxClassic.lua:622: in function `DynamicInit'
Interface\AddOns\DynamicBoxer\DBoxClassic.lua:212: in function `Sync'
Interface\AddOns\DynamicBoxer\DynamicBoxer.lua:1170: in function <Interface\AddOns\DynamicBoxer\DynamicBoxer.lua:1164>
(tail call): ?

Locals: self = DynamicBoxer_Status {
 ChangeScale = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:109
 Scale = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:105
 addLine = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:463
 addTexture = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:524
 lastAdded = <unnamed> {
 }
 PlaceGrid = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:328
 bg = <unnamed> {
 }
 addButtonBehavior = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:628
 setScale = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:194
 lastLeft = <unnamed> {
 }
 Modifiers = <table> {
 }
 font = GameFontHighlightLeft {
 }
 name = "DynamicBoxer_Status"
 numObjects = 3
 PlaceLeft = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:315
 addButton = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:654
 updateBorder = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:512
 addEditBox = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:664
 addMethods = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:364
 Place = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:282
 addSlider = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:582
 addAnimatedTexture = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:532
 tooltipTextMods = <table> {
 }
 bgColor = <table> {
 }
 leftMargin = 0
 tooltipText = "DynamicBoxer v3.04.02 help:

Shows your current dynamic mapping
(green number is known, ? is unknown)

Left click to invite
Middle click to disband
Right click for options

Drag the frame to move it anywhere.
Mousewheel to resize it

Click slot number see large on-screen slot information.
Hold Shift, Control, Alt keys for more tips."
 addText = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:405
 bgColorHex = "FF1933B2"
 children = <table> {
 }
 SetDefaultFont = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:95
 afterMoveCallBack = <function> defined @Interface\AddOns\DynamicBoxer\DBoxUI.lua:1124
 addDrop = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:760
 0 = <userdata>
 Init = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:113
 addTextButton = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:437
 calcCorners = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:122
 addCheckBox = <function> defined @Interface\AddOns\DynamicBoxer\MoLib/MoLibUI.lua:557
 defaultTooltipText = "DynamicBoxer v3.04.02 he

this would imply GetLeft for parent is nil and used in mirror; only use of mirror is through addTextButton
local w = f:addTextButton(left, nil, ttip, nil, "SecureUnitButtonTemplate"):Place(3, yOffset)

[mooreatv]

/dbox reset status + /reload fixed it; repro is not clear