I didn't want Etheryn in the party for this save but since a lot of nice powers and loot are locked behind her quests, I attempted to do them while leaving her unrecruited. The results were buggy.
For Specter of the Wyld, she was added to the party during the quest and was removed after it was finished. The issue is that now selecting the Character or Power page in the Journal crashes the game.
Error Message for Character Page:
Completing the dungeon in Ruins of Xadaron leaves Etheryn in the party despite not being recruited. This causes the Change Party menu at Waystones to crash the game in addition to the previous errors.
Error Message for Change Party:
The Demon of Ice quest has Etheryn join and leave the party like Specter does but I can't confirm if it causes the same crashes as Specter. The saves I can provide are all already bugged by Specter, but the circumstances are identical to Specter so I'd imagine Ice Demon would cause the same crashes if done before Specter.
For Specter of the Wyld, she was added to the party during the quest and was removed after it was finished. The issue is that now selecting the Character or Power page in the Journal crashes the game.
Error Message for Character Page:
Error Message for Powers Page:version: 0.6.31
TypeError: Cannot read property 'isCompanion' of undefined
at u.value (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/256.2af55323c3779289cac5.js:1:89539)
at Aa (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:69208)
at La (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:69003)
at bo (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:104404)
at fu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:95882)
at cu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:95807)
at nu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:92914)
at file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:44718
at t.unstable_runWithPriority (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:119640)
at Hl (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:44427)
version: 0.6.31
TypeError: Cannot read property 'filter' of undefined
at s.value (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/256.2af55323c3779289cac5.js:1:93007)
at s.value (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/256.2af55323c3779289cac5.js:1:95544)
at Aa (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:69208)
at La (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:69003)
at bo (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:104404)
at fu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:95882)
at cu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:95807)
at nu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:92914)
at file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:44718
at t.unstable_runWithPriority (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:119640)
Completing the dungeon in Ruins of Xadaron leaves Etheryn in the party despite not being recruited. This causes the Change Party menu at Waystones to crash the game in addition to the previous errors.
Error Message for Change Party:
version: 0.6.31
TypeError: Cannot read property 'active' of undefined
at i.value (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/826.a67054707d1fc752c9c6.js:1:3841980)
at i.value (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/826.a67054707d1fc752c9c6.js:1:3841572)
at i.value (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/826.a67054707d1fc752c9c6.js:1:3842419)
at Aa (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:69208)
at La (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:69003)
at bo (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:104404)
at fu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:95882)
at cu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:95807)
at nu (file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:92914)
at file:///C:/Users/Office/Downloads/CoC%20II-0.6.31-win/resources/app/737.33a8a15f6ee302d96f14.js:2:44718
The Demon of Ice quest has Etheryn join and leave the party like Specter does but I can't confirm if it causes the same crashes as Specter. The saves I can provide are all already bugged by Specter, but the circumstances are identical to Specter so I'd imagine Ice Demon would cause the same crashes if done before Specter.