Add Markdown render hooks for tables

Fixes #9316
Fixes #12811

hugolib/page__per_output.go

@@ -296,6 +296,8 @@ func (pco *pageContentOutput) initRenderHooks() error {
 				if id != nil {
 					layoutDescriptor.KindVariants = id.(string)
 				}
+			case hooks.TableRendererType:
+				layoutDescriptor.Kind = "render-table"
 			case hooks.CodeBlockRendererType:
 				layoutDescriptor.Kind = "render-codeblock"
 				if id != nil {
@@ -334,13 +336,23 @@ func (pco *pageContentOutput) initRenderHooks() error {
 
 			templ, found1 := getHookTemplate(pco.po.f)
 
-			if pco.po.p.reusePageOutputContent() {
+			if !found1 || pco.po.p.reusePageOutputContent() {
+				// Some hooks may only be available in HTML, and if
+				// this site is configured to not have HTML output, we need to
+				// make sure we have a fallback. This should be very rare.
+				candidates := pco.po.p.s.renderFormats
+				if pco.po.f.MediaType.FirstSuffix.Suffix != "html" {
+					if _, found := candidates.GetBySuffix("html"); !found {
+						candidates = append(candidates, output.HTMLFormat)
+					}
+				}
 				// Check if some of the other output formats would give a different template.
-				for _, f := range pco.po.p.s.renderFormats {
+				for _, f := range candidates {
 					if f.Name == pco.po.f.Name {
 						continue
 					}
 					templ2, found2 := getHookTemplate(f)
+
 					if found2 {
 						if !found1 {
 							templ = templ2