issues: documented GLIBCXX_3.4.21 not found

Dockerfile

@@ -23,6 +23,9 @@ RUN mkdir --parents /toontown-rewritten/launcher \
 RUN apt-get update && apt-get install --yes --no-install-recommends \
     xfonts-base `# launcher font`
 
+# debug
+#RUN apt-get install --yes --no-install-recommends file binutils ranger
+
 USER player
 VOLUME /toontown-rewritten/engine
 WORKDIR /toontown-rewritten/engine

ISSUES.md

@@ -0,0 +1,11 @@
+on some hosts:
+```
+libGL: dlopen /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so failed (/tmp/_MEIsdYgjK/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so))
+```
+
+possible workaround, seems to slow down game though:
+```
+ENV LD_PRELOAD=$LD_PRELOAD:/usr/lib/x86_64-linux-gnu/libstdc++.so.6:${LD_PRELOAD}
+```
+
+unclear why issue occurs on some hosts only