v6 upgrade guide - details for no hint path defined for namespace backpack error

Author: tabacitu

6.x/upgrade-guide.md

@@ -179,6 +179,10 @@ It's as easy as using an asset from a CDN, but it's much _much_ better than that
 
 <a name="step-18" href="#step-18" class="badge badge-secondary-soft" style="text-decoration: none;">Step 18.</a> **Have you developed any custom fields, columns, operations etc?** Rephrased: do you have anything inside your `resources/views/vendor/backpack/crud` directory? If so, we recommended you load your CSS & JS assets using `@basset('path/to/file.css')` instead of `@loadonce('path/to/file.css')` or `<link href="path/to/file.css">`. This will not only make sure that piece of JS/CSS/code is only loaded once per pageload, but it will also help serve all assets from one central location (your `storage/app/public` directory) which can be easily cleared using `php artisan basset:clear` to force cache-busting. You can find [more info about it here](https://github.com/laravel-backpack/basset).
 
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+<a name="step-18b" href="#step-18b" class="badge badge-secondary-soft" style="text-decoration: none;">Step 18.B.</a> If you have custom pages or custom operations, take particular note of the fact that the `backpack::` view namespace no longer exists. Most likely, when you try to use views from that namespace you will get an error saying "_No hint path defined for namespace [backpack]_". To fix this, the best solution is to change from using the namespace directly (eg. `@extends('backpack::blank')`) to using the backpack_view helper (eg. `@extends(backpack_view('blank'))`). That helper will make sure to load that blade file, from whatever theme is active right now (with fallback to the `vendor/backpack/ui` directory). Alternatively, if you only want to support ONE theme, you can replace that `backpack::` namespace with the namespace of the theme (eg. `backpack.theme-tabler::`).
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 <a name="step-19" href="#step-19" class="badge badge-danger" style="text-decoration: none;">Step 19.</a> If you've published and overriden any CRUD blade files, please take a look at the changes, and re-do them in your files too. We've done quite a few changes, to account for different themes in v6. For custom components, a good way to make them pretty would be to copy-paste HTML from [Tabler](https://tabler.io/preview), [CoreUIv4](https://coreui.io/demos/bootstrap/4.2/free/), [Backstrap](https://backstrap.net/) (depending on what theme you've chosen to use) or straight out [Bootstrap](https://getbootstrap.com/docs/5.3/examples/). // TODO: link to diff