If we select multiple textboxes in Draw, their context (right-click) menu lets us "Consolidate text" - making them into a single larger textbox.
Unfortunately, we don't have this functionality available in Impress. It should be made available on the context menu, like in Draw.
+1, the .uno:TextCombine control currently only works for a multi-textbox selection in Draw. Would be helpful to also have it available to use for working on Impress slides.
In sd "Consolidate Text" is provided by the .uno:TextCombine control. But attempting to customize and add the control to the Impress context menus or to a toolbar don't expose a functional widget. Seems like it could.
.uno:TextCombine in officecfg/registry/data/org/openoffice/Office/UI/DrawImpressCommands.xcu is used at sd/uiconfig/sdraw/menubar/menubar.xml and sd/uiconfig/sdraw/popupmenu/multiselect.xml and could be easily added to sd/uiconfig/simpress/menubar/menubar.xml and sd/uiconfig/simpress/popupmenu/multiselect.xml (customization works out of the box for me).