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One time activation 
- To activate the gadget
- In "Preferences" : "gadgets" tab, "Tools for categories" section: click "Cat-a-lot" and hit "Save" at bottom of page.
Moving files between categories, and removing files from a category 
- Turn on the gadget: after activation, you will see a little post-it-note labeled "cat-a-lot" in the lower-right corner of every category page. This box will stay in that corner, independent of your position on the page. If the note doesn't appear, try to purge the cache of your browser. Click it to start the tool. this will show a box like the one in the Figure 2.
- Select files: You can also select individual image thumbnails by clicking in the white space of the thumbnail description. The description background will turn green to indicate that this image is now selected. Another click will de-select it, and the background turns white again. You can also select/de-select all visible images by clicking select all / none in the cat-a-lot box. To select multiple files "in a row" (fig.), first select file A, then hold down ⇧ Shift and click at the white space of file B. All files between A and B now got the state of file B.
- Select destination category: Initially tool loads the current category (→), its parent-category (↑) and subcategories (↓). You can navigate through the category tree by clicking on a category name. Only the category list in the box will change, you will stay on the original page. Instead of navigating through clicking, you can also enter a category name (i.e. "Lions", not "Category:Lions") in the white text field above the list and pushing "ENTER" on your keyboard. The named category will then show up in the middle of the tree below, with its parents and children.
- Perform the Operation: Click on Move or Copy links next to destination category and the selected images will be moved or copied from the current into destination category. The difference between move and copy is that copy leaves a copy in a source category. Alternatively you can click on "Remove from this category" link in order to remove all selected files from the current category. A progress indicator will be shown. After all images were processed, a report is shown including possible problems.
Categorizing search results 
- Perform the search, for example for term "Seneca Rocks"
- Turn on the gadget: by clicking little post-it-note labeled "cat-a-lot" in the lower-right corner of the search result page. Your screen should look similar to Figure 3.
- Select destination category: by entering a category name in the white text field in top of cat-a-lot box and pushing "ENTER" on your keyboard. Your screen should look similar to Figure 4.
- Perform the Operation: by clicking "Add" link next to destination category and the selected files will be added to that category, if they do not already belong to it.
There is preferences menu in Cat-a-lot:
- Whether to mark edits as minor
- Whether to allow editing pages that aren't files or in gallery boxes
- Whether to do clean up
- Numbers of sub-categories to show
Open bugs & features 
- Note: Add signature to entries below. -~~~
- Check for empty lines (what's the current behaviour?)
- Make crosssections (For example, moving all media in "Category:Sailing ships" and "category:Ships of the Netherlands" into "category:Sailing ships of the Netherlands" (removing both prior categories).) Reported by Ibn Battuta.
- Minor change by default (Reported by Ibn Battuta). ??? Pls explain. --Rillke(q?)
- More sophisticated categories handling - Example: removing ALL categories from file(s) BUT a selected category. --Kozuch.
- Spinoff: Edit-a-lot for various text replacements? -DieBuche (talk) — done by VisualFileChange RE rillke questions?
- Add Preference screen:
- Keyboard navigation. -(Jean-Fred).
- #Copying images from categories added through templates.
- A stop button to abort an operation in progress (and ideally offer to revert changes already made). Rd232 (talk) 18:13, 19 November 2011 (UTC).
- Remove duplicate categories from pages, if the duplicate category is changed instead of changing both categories (including the duplicate one)
- Remove (selectable) more than one category. -- Perhelion (talk) 22:44, 3 October 2012 (UTC)