try to reduce memory leak (ticket #33016)

try to reduce memory leak (ticket #33016)

 143850 words of node memory still in use:
   22 hlist, 2 vlist, 7 rule, 12 glue, 117 kern, 5 penalty, 2 glyph, 63253 attri
bute, 2452 glue_spec, 3084 attribute_list, 3 action, 1 write, 1 pdf_literal, 1 p
df_setmatrix, 2 pdf_save, 2 pdf_restore, 37 user_defined nodes
   avail lists: 1:5,2:157048,3:3623,4:16650,5:6634,6:4956,7:10016,8:81,9:9416,10
:680