This patch adds support for Poppler 0.76 and later.

Taken from upstream:
<https://gitlab.com/inkscape/inkscape/commit/e831b034746f8dc3c3c1b88372751f6dcb974831>

diff --git a/src/extension/internal/pdfinput/pdf-parser.cpp b/src/extension/internal/pdfinput/pdf-parser.cpp
index 8484984bdf..4f798e35bf 100644
--- a/src/extension/internal/pdfinput/pdf-parser.cpp
+++ b/src/extension/internal/pdfinput/pdf-parser.cpp
@@ -421,7 +421,7 @@ void PdfParser::parse(Object *obj, GBool topLevel) {
 	error(errInternal, -1, "Weird page contents");
     	return;
   }
-  parser = new Parser(xref, new Lexer(xref, obj), gFalse);
+  parser = new _POPPLER_NEW_PARSER(xref, obj);
   go(topLevel);
   delete parser;
   parser = nullptr;
diff --git a/src/extension/internal/pdfinput/poppler-transition-api.h b/src/extension/internal/pdfinput/poppler-transition-api.h
index 61a15083a0..5e8bc4ae90 100644
--- a/src/extension/internal/pdfinput/poppler-transition-api.h
+++ b/src/extension/internal/pdfinput/poppler-transition-api.h
@@ -14,6 +14,13 @@
 
 #include <glib/poppler-features.h>
 
+#if POPPLER_CHECK_VERSION(0, 76, 0)
+#define _POPPLER_NEW_PARSER(xref, obj) Parser(xref, obj, gFalse)
+#else
+#define _POPPLER_NEW_PARSER(xref, obj) Parser(xref, new Lexer(xref, obj), gFalse)
+#endif
+
+
 #if POPPLER_CHECK_VERSION(0, 72, 0)
 #define getCString c_str
 #endif
hash.hh?id=81d2fc9ffc3dbfc0fce2b85e267b18efbe24851a'>commit</a><a href='/guix/diff/nix/libutil/hash.hh?id=81d2fc9ffc3dbfc0fce2b85e267b18efbe24851a'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/nix/libutil/hash.hh'>
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<tr><td><span title='2020-06-27 23:42:20 +0200'>2020-06-27</span></td><td><a href='/guix/commit/nix/libutil/hash.hh?id=8e6c1415d87272c0221ce328715fc0dd1dd3e032'>daemon: Recognize SHA3 and BLAKE2s.</a><span class='msg-avail'>...<span class='msg-tooltip'>* nix/libutil/hash.hh (HashType): Add htSHA3_256, htSHA3_512, and
htBLAKE2s_256.
* nix/libutil/hash.cc (parseHashType, printHashType): Recognize them.
* tests/store.scm ("add-to-store"): Test these algorithms.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-06-27 23:42:20 +0200'>2020-06-27</span></td><td><a href='/guix/commit/nix/libutil/hash.hh?id=3fb6b8f30444d41963ba5bdd441123a6d2df17bd'>daemon: Map directly to gcrypt hash functions.</a><span class='msg-avail'>...<span class='msg-tooltip'>* nix/libutil/hash.hh (HashType): Map directly to GCRY_MD_ values.
(md5HashSize, sha1HashSize, sha256HashSize, sha512HashSize): Remove.
* nix/libutil/hash.cc (Hash::Hash): Use 'gcry_md_get_algo_dlen'.
</span></span></td><td>Ludovic Courtès</td></tr>