diff --git a/multimedia/libwebm/Makefile b/multimedia/libwebm/Makefile
index dca9110a3cf3..8efa1ebc99b1 100644
--- a/multimedia/libwebm/Makefile
+++ b/multimedia/libwebm/Makefile
@@ -1,24 +1,25 @@
 PORTNAME=	libwebm
 DISTVERSIONPREFIX=	libwebm-
 DISTVERSION=	1.0.0.32
+PORTREVISION=	1
 CATEGORIES=	multimedia
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	WebM video format
 WWW=		https://www.webmproject.org/
 
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE.TXT
 
 USES=		cmake:testing compiler:c++11-lang
 
 USE_GITHUB=	yes
 GH_ACCOUNT=	webmproject
 GH_TUPLE=	google:googletest:release-1.11.0:gtest/../googletest
 
 CMAKE_ON=	ENABLE_IWYU \
 		ENABLE_WEBM_PARSER \
 		BUILD_SHARED_LIBS
 CMAKE_TESTING_ON=	ENABLE_TESTS # it's not clear how to run tests, some test executables show failures when run
 
 .include <bsd.port.mk>
diff --git a/multimedia/libwebm/files/patch-CMakeLists.txt b/multimedia/libwebm/files/patch-CMakeLists.txt
new file mode 100644
index 000000000000..4b74f52703d2
--- /dev/null
+++ b/multimedia/libwebm/files/patch-CMakeLists.txt
@@ -0,0 +1,43 @@
+--- CMakeLists.txt.orig
++++ CMakeLists.txt
+@@ -364,7 +364,10 @@
+ if(ENABLE_WEBM_PARSER)
+   include_directories(webm_parser webm_parser/include)
+   add_library(webm_parser OBJECT ${webm_parser_sources})
+-  target_sources(webm PUBLIC $<TARGET_OBJECTS:webm_parser>)
++  # Wrap in BUILD_INTERFACE so the object files are compiled into the webm
++  # library but the $<TARGET_OBJECTS:...> expression does not leak into the
++  # installed/exported interface, where consumers cannot evaluate it.
++  target_sources(webm PUBLIC $<BUILD_INTERFACE:$<TARGET_OBJECTS:webm_parser>>)
+ 
+   add_executable(webm_parser_demo ${webm_parser_demo_sources})
+   target_link_libraries(webm_parser_demo LINK_PUBLIC webm)
+@@ -459,8 +462,13 @@
+ # webm_parser headers are rooted at webm/.
+ set_target_properties(webm PROPERTIES PUBLIC_HEADER
+                                       "${webm_parser_public_headers}")
++# Expose the installed include root so downstream consumers can reference
++# headers with their prefix, e.g. <mkvmuxer/mkvmuxer.h> or <common/webmids.h>.
++target_include_directories(webm INTERFACE
++  $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/webm>)
+ install(
+   TARGETS webm
++  EXPORT webmTargets
+   ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+   LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+   RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+@@ -474,3 +482,14 @@
+         DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/webm/mkvmuxer)
+ install(FILES ${mkvparser_public_headers}
+         DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/webm/mkvparser)
++
++# Install a CMake package configuration so downstream projects can locate
++# libwebm with find_package(webm) and link against the webm::webm target.
++install(EXPORT webmTargets
++        FILE webmTargets.cmake
++        NAMESPACE webm::
++        DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/webm)
++file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/webmConfig.cmake"
++     "include(\"\${CMAKE_CURRENT_LIST_DIR}/webmTargets.cmake\")\n")
++install(FILES "${CMAKE_CURRENT_BINARY_DIR}/webmConfig.cmake"
++        DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/webm)
diff --git a/multimedia/libwebm/pkg-plist b/multimedia/libwebm/pkg-plist
index 873ddd836c4b..27d3cc38e6a7 100644
--- a/multimedia/libwebm/pkg-plist
+++ b/multimedia/libwebm/pkg-plist
@@ -1,18 +1,21 @@
 include/webm/buffer_reader.h
 include/webm/callback.h
 include/webm/common/webmids.h
 include/webm/dom_types.h
 include/webm/element.h
 include/webm/file_reader.h
 include/webm/id.h
 include/webm/istream_reader.h
 include/webm/mkvmuxer/mkvmuxer.h
 include/webm/mkvmuxer/mkvmuxertypes.h
 include/webm/mkvmuxer/mkvmuxerutil.h
 include/webm/mkvmuxer/mkvwriter.h
 include/webm/mkvparser/mkvparser.h
 include/webm/mkvparser/mkvreader.h
 include/webm/reader.h
 include/webm/status.h
 include/webm/webm_parser.h
+lib/cmake/webm/webmConfig.cmake
+lib/cmake/webm/webmTargets-%%CMAKE_BUILD_TYPE%%.cmake
+lib/cmake/webm/webmTargets.cmake
 lib/libwebm.so