Cannot read property of 'replace' of undefined stack

I am getting a Cannot read propery of 'replace' of undefined stack error. It occurs in all browsers that I have tested this log is from Firefox. I have cleared cookies then run it again, I've created new characters and tried again. Chrome seems to run this faster than Firefox. Not sure what it means exactly. Here is the console log: "CLICKED" app.js:35:31749 "Updating character sheet values" app.js:36:6383 "ERROR parsing formula: undefined" app.js:36:9382 TypeError: formula is undefined Stack trace: d20.models.Character&lt;.autoCalcFormula@<a href="https://app.roll20dev.net/assets/app.js?1430240454:36:24786" rel="nofollow">https://app.roll20dev.net/assets/app.js?1430240454:36:24786</a> d20.models.CharacterView&lt;._updateSheetValues/&lt;@<a href="https://app.roll20dev.net/assets/app.js?1430240454:36:9219" rel="nofollow">https://app.roll20dev.net/assets/app.js?1430240454:36:9219</a> k.forEach@<a href="https://app.roll20dev.net/assets/base.js?1429019847:1:1713" rel="nofollow">https://app.roll20dev.net/assets/base.js?1429019847:1:1713</a> d20.models.CharacterView&lt;._updateSheetValues@<a href="https://app.roll20dev.net/assets/app.js?1430240454:36:8487" rel="nofollow">https://app.roll20dev.net/assets/app.js?1430240454:36:8487</a> k.debounce/&lt;/n@<a href="https://app.roll20dev.net/assets/base.js?1429019847:1:7634" rel="nofollow">https://app.roll20dev.net/assets/base.js?1429019847:1:7634</a> app.js:36:9423 "Took 81ms" app.js:36:10161 It seems to happen when I try and change the value select boxes inside of repeating fields. I am not sure what is causing it, but everything seems to run just fine even with the error. However, because it seems to be an issue within repeating sections I'd rather find out if its serious before I start copy and pasting sections of code to use elsewhere. So, basically, is this serious or should I just ignore this error and continue on. If it is serious, what exactly does this mean? I know that most of my posts lately seem to be asking for help, I'm sure it must be getting old but I hope at least this helps others as well.

Can you give more background on when and where this is happening. What character sheet are you using. Do you have any API scripts active in your campaign? Does this happen in all campaigns and with all characters?

I am using a custom character sheet that I am creating. I have no API running, and all characters within the test campaign.

And this isn't affecting other campaigns not using your custom sheet? So, it's probably something to do with the setup of your custom sheet?

Well, yes I'm sure it is an issue with my campaign set up, but this error is a little on the technical side. I was just wondering if someone with technical knowledge could give a small explaination of what this error means in plain english so I could go about fixing it. As it stands I have 5000+ of code that this could be attached to not to mention something that might be going on in the base.css and app.css which I cant do anything with. Or, even better tell me this error can simply be ignored and is nothing really important and can be safely ignored.

Based on the following 2 lines, I speculate you have an error in one of your auto calculated fields, specifically either something is empty that should have a value, or is referencing another field that doesn't exist yet. "ERROR parsing formula: undefined" app.js:36:9382 TypeError: formula is undefined

When a field in a character sheet it changed, it also looks for any other attributes that depend on that attribute and updates them as well. The error is happening when that process fails. Edit: Probably specifically from a disabled field.