add warning about .notion-enhancer folder

Author: dragonwocky

Diff for: about/contributing.md

@@ -244,7 +244,7 @@ Once relaunched, Notion will be running a version of the
 notion-enhancer with your changes included. You will need to
 repeat this every time you make changes.
 
-> Note: this chain of arguments is intended for development/testing of
+> **Note:** this chain of arguments is intended for development/testing of
 > mods only. It overrides previous enhancements and skips backup to
 > re-insert the notion-enhancer quickly when modifying the contents
 > of the `desktop/insert` folder.

Diff for: advanced/tweaks.md

@@ -20,7 +20,7 @@ injecting custom CSS into the client:
    its options in the sidebar. Click the "Upload file..." button beneath
    the "css insert" option and select the `.css` file you created.
 
-   > Note: previously, uploads were linked to the original files and
+   > **Note:** previously, uploads were linked to the original files and
    > would reflect changes. This is no longer the case - uploaded files are
    > stored in memory and must be re-uploaded to reflect edits.
    >

Diff for: getting-started/installation.md

@@ -16,7 +16,16 @@ will never be supported.
 Once you've installed the notion-enhancer, read the
 [Basic Usage](./basic-usage.md) page to get started with it.
 
-> Note: though it is possible to have both vanilla Notion
+> **Warning:** the new version of the notion-enhancer handles storing local
+> configuration differently to previous versions. If you used notion-enhancer
+> prior to v0.11.0, please delete the `.notion-enhancer` folder to prevent any
+> issues that may arise.
+>
+> It can be found within your home/user folder, e.g. `~` on macOS and Linux
+> or `C:\Users\YourName` on Windows (enabling the "show hidden files" option
+> in your file manager may be necessary).
+
+> **Warning:** though it is possible to have both vanilla Notion
 > and enhanced Notion installed at once, running both at
 > once may cause problems and should never be done.