Generally to select multiple rows in a block, you select the 1st row then the last row with the SHIFT key.
Faster solution you can click on the small red rectangle present in the left corner of each block separator.
In all the tables that contain separators, you will find these small red rectangles, for example in PrestaPricing, in the table of declinations, we have selected all the lines of the block by clicking on the red square highlighted in yellow:
This red rectangle, you will find it in the table of images, declensions and also in PrestaCategory in the list of products. In the example below, in PrestaCategory we have selected all the lines of the 5 blocks by clicking on the red rectangles of each block:
Next week we will discuss a more technical topic with PrestaCategories, how to get out of this headache: we have products that are assigned to a default category that no longer exists and we can not assign them to a new category by Default.
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