📝 Upgrading of TiddlyWiki Classic is known to fail with some savers. This plugin is meant to fix this for some cases: at least for Timimi or MTS 1.7.0 and above.
It also adds optional upgrade autocheck on start; tiddlers and fields sorting so that the changes are easier to review.
It is tested at least on upgrading 2.6.5, 2.9.2, 2.9.3 → 2.9.3, 2.9.4. Presumably, once it covers more savers, it will be merged into the core.
🛍️ Available to install via ExtensionsExplorerPlugin, like many others (to find it, install the central collection and YLExtensionsCollection from it).