Skip banner functionality for Canvas views (#122)

src/editing/extensions/bannerExtender.ts

@@ -1,5 +1,6 @@
 import { EditorState, StateEffect, Transaction } from '@codemirror/state';
 import isEqual from 'lodash/isEqual';
+import { editorInfoField } from 'obsidian';
 import { extractBannerDataFromState, shouldDisplayBanner } from 'src/bannerData';
 import bannerField from './bannerField';
 import {
@@ -12,13 +13,15 @@ import {
   upsertBannerEffect
 } from './utils';
 
+// Get an upsert/remove effect depending if banner data should be displayed
 const getEffectFromData = (state: EditorState): StateEffect<BannerMetadata> => {
   const bannerData = extractBannerDataFromState(state);
   return shouldDisplayBanner(bannerData)
     ? upsertBannerEffect.of(bannerData)
     : removeBannerEffect.of(null);
 };
 
+// Helper to check if banner data change between transactions
 const didBannerDataChange = (transaction: Transaction): boolean => {
   const { docChanged, state } = transaction;
   if (!docChanged) return false;
@@ -33,6 +36,9 @@ effects to `bannerField` */
 const bannerExtender = EditorState.transactionExtender.of((transaction) => {
   const { effects, state } = transaction;
 
+  // Only run on Markdown panes (skips Canvas views)
+  if (state.field(editorInfoField).leaf === undefined) return null;
+
   if (hasEffect(effects, openNoteEffect)) {
     console.log('open note!');
     const newEffects = [];

src/editing/extensions/utils.ts

@@ -31,7 +31,7 @@ export const getBanner = (state: EditorState) => {
 
 export const destroyBanner = (state: EditorState) => {
   const { id } = state.field(editorInfoField).leaf;
-  const banner = getBanner(state);
+  const banner = leafBannerMap[id];
   banner.$destroy();
   delete leafBannerMap[id];
 };