Correction
Editing a translation
Strings stored in XLIFF format (core, modules and recent themes) are editable straight from the results list: you enter the new value, it is written to the language file and marked as validated. Other entries link, directly, to PrestaShop's native translation screen, already positioned.
An inline edit modifies the language file. After a theme or module update that regenerates those files, re-check your edits — the "validated" flag protects them from most regenerations, but not from a full file replacement.